2.1. Family background

William Robert Evitt II was born on 9 December 1923 in Baltimore, Maryland, United States (Figure 1), and was named after his paternal grandfather. He was the only child of Raymond Wilson (‘Wils’) Evitt and Elsa Schwarz Evitt, and was always known as Bill. Raymond Evitt had British heritage; by contrast, his mother's family, as the name Schwarz strongly suggests, was German and they were part of a large German community in Baltimore. Bill's maternal grandfather owned the Schwarz Toy Store in Baltimore; unfortunately, he died when Bill was only two years old. Bill also hardly knew his maternal grandmother, who died two years after her husband's passing.

Bill's father had studied civil engineering at Johns Hopkins University in Baltimore, but never practiced because he undertook military service in World War I immediately after graduating. Raymond served as a pilot for the final months of the war, joining Edward V. Rickenbacker's famous 94^th Fighter Squadron (‘Hat in the Ring’) of the US Army Air Force (Woolley 2001) and was based in France. After the conflict ended, Raymond found it difficult to find a meaningful career, and took up jobs in insurance and real estate. Elsa Evitt was a talented artist, specialising in oil painting (Figures 2, 3), who trained at the Maryland Art Institute in Baltimore as did her mother before her.

Bill first lived in the house belonging to his maternal grandparents, the Schwarzes, until the age of four. The house was 3 Prospect Circle in Windsor Hills, one of the western suburbs of Baltimore. It was a large house built into a steep hillside which backs onto Gywnn's Falls, a small river which drains into Chesapeake Bay. The younger daughter of the original owners, and her husband, Henry Stanwood, became lifelong friends of Bill’s parents.

2.2. An idyllic childhood at the Old Stone House

In 1927, Raymond Evitt finally obtained a relatively well-paid job with the Annapolis Dairy Products Company. Consequently, the Evitt family moved out to the open countryside on the relatively flat Atlantic Coastal Plain north of Annapolis and south of Baltimore to a region which has long since been subsumed into the Baltimore-Washington, DC Metropolitan Area (Figure 1). On 28 July 1928 they began a tenancy of an early eighteenth-century stone-built house on Old Annapolis Road in what is now Severna Park in Anne Arundel County, very close to the main Baltimore-Annapolis Boulevard (now the Ritchie Highway). This imposing residence was always known to the Evitt family as the Old Stone House (Figure 4).

Table 1.

A tabulated synopsis of Bill Evitt's principal career milestones.

The land was apparently first owned by a Richard Beard in 1687, and known as Huckleberry Forest. This tract was purchased by a Mr Robinson in 1702, and the Old Stone House was built of the local field stone during that year. The grandson of Mr Robinson, Elijah ‘Robison’, sold the property to John Tydings in 1837. The son of the latter, John Lewis Tydings, married Laura C. Robinson, and their daughter, Laura Tydings Garcelon, was the last member of this dynasty to own the Old Stone House and the surrounding land. Mrs Garcelon did not wish the estate to be sold during her lifetime. Consequently, the Evitts paid her a nominal rent for the house and garden, and had the free use of the adjacent fields and pine forest. Bill's parents eventually took up their option to buy the entire property in 1954 following the death of Laura Garcelon. The Old Stone House backs onto Cattail Creek to the south; this is a distributary of the Magothy River, one of the many tributaries of Chesapeake Bay (Figure 1D). In earlier times, the area had been extensively farmed, despite the very sandy soil. Bill's parents sold 140 acres of the land to the developer of Berrywood during 1964. Raymond Evitt eventually sold the house and the remainder of the plot in June 1978 for the development of Berrywood West, and moved to a retirement home. He had lived in the Old Stone House for 51 years. The present owners of the residence, which is now known as the Robinson House and is on Evitt Court (Figure 1D), have successfully applied for its placement in the National Historic Place Register (reference number 09000782).

Maryland is, of course, a mid-Atlantic state, but in the 1920s in cultural terms it was very ‘southern’, with a large, mostly poor and highly segregated black population. Indeed, during the summer of 1929 the Evitts hired Mandy, a black live-in servant. Life in rural Anne Arundel County at that time was ‘very country’, and hugely different to that of today. For example the only air conditioning was supplied by fans, and cooking was done on a paraffin (kerosene) stove. It was a 20-minute electric streetcar ride to Annapolis, and Baltimore was a 45-minute car journey away. The nearby two-lane roads were very winding. Petrol (gasoline) was 20 cents per gallon, and was supplied from a handpumped overhead tank. Bill enthusiastically helped his parents with the extensive renovations they made to the Old Stone House. The Evitts kept several pets, including Nannette the German Shepherd dog, who they brought with them as a puppy when they moved to the country from Baltimore. Nannette probably saved the Old Stone House from a major fire by waking Elsa Evitt from a nap while the water heater in the basement was badly overheating. Other pets included Nannette's puppies and their offspring, Billy-Bill the goat and Funny-Face the donkey (burro). The young Bill (Figure 2) was tasked with feeding and watering all the animals.

Figure 1.

Four maps at various scales of the eastern United States to illustrate key localities pertaining to Bill Evitt's early life (section 2). A, eastern North America; B, the central-eastern United States centred around Washington, DC, and Chesapeake Bay, Maryland; C, the mouth of the Magothy River in northern Chespeake Bay; D, Cattail Creek close to the mouth of the Magothy River immediately south of the Old Stone House, which now is on Evitt Court.

During this time, Bill had no friends from his peer group nearby, and consequently was a very independent boy. He attributed his love of the natural sciences to his rural upbringing, where he would wander the disused farm buildings and woodland around the family home. Bill helped his parents with several practical hobbies such as copper plate etching, gem faceting, metalwork, pottery, silver casting, and wood carving and turning. Items made by the Evitt family were only sold during the worst years of the Great Depression in the mid 1930s. It seems likely that activities such as making silver jewellery allowed Bill to develop his dextrous skills in the fine-scale manipulation of fossils that he used to great effect during his career in palaeontology.

Figure 2.

Bill Evitt at about nine years old, painted in oils by his mother, Elsa Evitt, around 1933. The image is reproduced with the approval of the Evitt family.

2.3. Early Education (1930–1940)

In 1930, Bill Evitt commenced his elementary education in a small, three-room schoolhousc in the then small community of Sevema Park, 3 km from the Old Stone House (Figure 1C). The young Bill was extremely studious, and was quickly promoted from the second grade to the fourth. He was never an enthusiastic participant in team sports. Perhaps because of this, together with his academic nature, he was somewhat of a loner at school. Bill did feel that, as he was an only child living in a rural setting with little interaction with a peer group, he became relatively ill equipped to relate easily to his peers in later life. He openly admitted to finding some social occasions stressful.

Figure 3.

Bill Evitt in profile at about fourteen years old, painted by his mother, Elsa Evitt, around 1938. The image is reproduced with the approval of the Evitt family.

Bill commenced his four years of high school in 1936. He travelled 17 km each way to a high school in the western part of Annapolis. Bill studied biology, chemistry, English, French, history, Latin, maths, physics and social science. He found that his high school biology classes, allied with the microscope he received one Christmas, confirmed his profound interest in nature. Bill immediately took to microscopy and used the small (∼20 cm high) transmitted light microscope, which magnified between 25 and 150×, to examine microscopic organisms from the ponds and streams near the Old Stone House and Cattail Creek. Occasionally he would project images onto a small screen to show his parents images of microorganisms. Bill also enjoyed studying chemistry. In particular, he loved to observe the growth of crystals from the evaporating solutions of various water-soluble substances in his much-loved chemistry set using his first microscope. He also loved to observe the changing shapes of iodine crystals in a glass vial that he had filled. Bill frequently indulged in more dangerous experiments in chemistry, such as boiling mercury in a test tube using a Bunsen burner! Furthermore, his Latin classes helped Bill with the use of Latinised terminology during his later career. He later said that his vocation to teach was awakened during his high school days. At this time he also learned how to type on his maternal grandmother's old upright Remington typewriter. Bill developed his great interest in music while at high school, and recalls this starting with listening to mostly operatic recordings. He clearly recalled the events leading to the outbreak of World War II in the summer of 1938, and how this awakened his interest in current affairs.

Figure 4.

An etching of the Evitt family residence, the Old Stone House, in Severa Park, Anne Arundel County, Maryland, made by Bill's mother, Elsa Evitt, around 1933. The image is reproduced with the approval of the Evitt family.

2.4. Nascent interest in geology

The Evitt family owned a 15-m, ketch-rigged, cx-World War I patrol boat named Wanderer. This boat was fitted with a small auxiliary engine, and was originally bought by Bill’s paternal grandfather after the hostilities ceased. It was sailed around to Cattail Creek from Baltimore. Wanderer was moored at a small wharf on the Old Stone House property, and the Evitts used it for both day-trips and annual family holidays, where they sailed this rather clumsy vessel in Chesapeake Bay and its many tributaries (Figure 1B). Most of the extended trips were to the unspoilt countryside on the eastern shore of Maryland on Chesapeake Bay. Bill's introduction to geology and fossils came with his father at the famous Calvert Cliffs on the eastern side of the Calvert Peninsula in west Chesapeake Bay (Figure 1B) during his high school years. These successions include the type section of the Lower to Middle Miocene Calvert Formation; this unit comprises highly fossiliferous sands with interbedded clays. The fauna is dominated by abundant echinoids, molluscs, shark teeth and vertebrate fossils (Yokes 1957). Bill collected many specimens from the Calvert Formation, and the fossils of Calvert Cliffs undoubtedly helped to inspire him to study geology at university. The father and son team also collected unconsolidated siliciclastic material from the pyrite beds in the Upper Cretaceous (Turonian—Santonian) Magothy Formation (Darton 1893; Owens et al. 1970; Jengo 1995) from the banks of the River Magothy in Maryland, close to the Old Stone House. Many years later, John P. Kokinos undertook a master's thesis at Stanford University on the palynology of these samples (Kokinos 1987). The fact that Bill kept and curated the Magothy Formation material for close to 50 years is a testament to his sustained commitment to his sound geological collecting practices.

Raymond and Elsa Evitt were always very supportive of their only son's great interest in the natural world. As mentioned previously, they bought him a microscope and Bill recalled observing for hours the fascinating spiralling and twisting motion of the freshwater/brackish dinoflagellate Ceratium hirundinella (Plate 1, figure 3; Plate 2, figure 1), which he had caught on the boat dock at Cattail Creek. It is remarkable that Bill began his studies of dinoflagellates during the 1930s while still a young schoolboy! Apparently, his earliest publication was a one-paragraph note describing an unusual morphological phenomenon on a cactus plant in a monthly journal on cacti and succulents. Unfortunately, despite the best efforts of the authors and the Evitt family, this contribution cannot be tracked down.

Plate 1.

Four of the 35-mm transparency slides included in the ringbound file of course materials that Bill Evitt provided to participants of the two-week Teaching Conferences on Fossil Dinoflagellates (section 10). These slides accompanied the practical exercises and the specimens for study. Figures 1 to 3 are modern thecate forms and figure 4 is a Paleocene dinoflagellate cyst. All of the images are reproduced with the approval of the Evitt family.

Figure 1. A theca of Protoperidinium leonis; modern, marine, California. This specimen, which is in ventral view, was captured using a plankton net and was slide 1. Note the hyaline (somewhat glassy) appearance, the prominent hexagonal 1' plate which is positioned midventrally, the laevorotatory (descending) cingulum, and the slightly sloping and highly indented sulcus which is largely on the hypotheca. The overall length is 90 µm, and the specimen is 85 µm in maximum width.

Figure 2. A resting cyst within a theca of Protoperidinium leonis; modern, marine, California. This theca and cyst combination, which is in dorsal view, was captured using a plankton net and was slide 2. Note the contrast in appearance between the hyaline theca and the brown, somewhat granular resting cyst. The outer wall of the resting cyst is in close proximity to the inner surface of the theca; despite this, the rounded antapical horns of the cyst contrast markedly with the very sharply pointed horns of the theca. The uninterrupted dorsal part of the reflected cingulum is readily discernible on the resting cyst. The overall length of this specimen is 85 µm, and it is 80 µm in maximum width.

Figure 3. A theca of Ceratium hirundinella; modern, freshwater, California. The specimen, which is in ventral view and high focus, was captured using a plankton net and was slide 3. Note the hyaline appearance, the reticulate wall texture, the well-developed cingulum and the four horns. The largest horn is apical in position and the others are all hypothecal (i.e. one antapical and two postcingular). The smaller of the postcingular horns is the left one (Evitt & Wall 1975, fig. 1). This is a corniform dinoflagellate organisation principally due to the prominent horns. The corniform grouping of Evitt (1985) exhibits an extremely distinctive tabulation style with an extensive concave ventral area formed of the 6″, 6c and 6'″ plates which are relatively thin (Evitt & Wall 1975). The overall length of this specimen is 145 µm, and it is 80 µm in maximum width (including horns).

Figure 4. Dracodinium samlandicum; ventral view, median focus; Eocene, unnamed borehole, Maryland. This specimen was illustrated as Wetzeliella sp. in the course manual as slide 20. Note the proximochorate and circumcavate/cornucavate cyst organisation. The wall of the microgranulate ovoidal endocyst is markedly thicker than that of the spinose subpentagonal pericyst. It has a characteristic anterior intercalary (type A) latiepeliform archaeopyle formed by the loss of the distinctly four-sided (quadra) plate 2a in both cyst walls. The endoperculum and perioperculum are both displaced and are present. The endoperculum is within the hypocyst, and appears to have fallen back into the endocyst. By contrast, the perioperculum lies largely in the epicyst; it is offset to the left-hand side of the cyst; it may have become lodged between the periphragm and endophragm. The archaeopyle is the principal indicator of tabulation; however, the cingulum is also vaguely discernible in this specimen. This species is typical of the Palaeogene peridiniacean subfamily Wetzelielloideae, which was recently comprehensively reviewed by Williams et al. (2015). The overall length of this specimen is 125 µm, and its maximum width is 127 µm.

The Evitt family were clearly very close; Bill recalled that he was treated as an equal, and the three continued to explore eastern Canada, Maryland, New York State, Ohio and Virginia while Bill was an undergraduate student at Johns Hopkins University.

3.1. Introduction

Bill Evitt was an undergraduate and graduate student at Johns Hopkins University, Baltimore, between 1940 and 1948. Johns Hopkins has an excellent reputation for both research and teaching. It was also conveniently close to the Evitt family home, and furthermore Bill's father had studied there. Bill commuted to college daily and lived with his parents in the Old Stone House during his sojourn at Johns Hopkins, with the exception of his wartime service between June 1943 and January 1946.

3.2. Chemistry to geology — the undergraduate years and the pre-war period (1940–1943)

Bill applied to become an undergraduate student, majoring in chemistry, at Johns Hopkins University to formally commence studies in autumn 1940. In those days, undergraduate tuition fees were only US $250 per semester. Bill's application was successful, and he joined the Alpha Delta Phi fraternity at Johns Hopkins. This group has a strong literary tradition and membership in it gave Bill a strong connection with his fellow students, which he badly needed because he lived off campus. Once Bill was accepted, he enrolled in a German course during mid 1940 because he did not have a summer job. This far-sighted strategy enabled Bill the freedom to take purely science courses during his freshman year. At this time he was considering becoming a chemist, having enjoyed studying chemistry at high school. However, probably based on the enjoyable geological fieldwork at the Calvert Cliffs as a schoolboy, and because his father regretted not studying earth sciences, he also enrolled in a subsidiary course in elementary geology. This decision was to prove pivotal. In his freshman year, Bill only scraped a pass in chemistry. By contrast, he loved geology immensely, especially palaeontology, and excelled in it. Bill also enjoyed studying crystallography and mineralogy. In particular, he found the classification of the various wooden models of crystals fascinating, and this probably contributed to his interest in biological classification, form and symmetry in his later career. Unsurprisingly, Bill was beginning to consider majoring in geology after his freshman year. In 1941, he undertook another summer school in order to be more flexible in his remaining time as an undergraduate.

Plate 2.

Three low-magnification photomicrographs of microscope slides distributed by Bill Evitt at his Teaching Conferences on Fossil Dinoflagellates (section 10).

Figure 1. A group of several dissected plates of Ceratium hirundinella from a lake in California. The thecae were treated with sodium hypochlorite solution to dissociate the plates; hence, individual elements can be studied in detail. This is Stanford University palynology sample PL 5134. The England Finder coordinate is L35/3 and the image was taken using differential interference contrast (DIC). This slide was distributed at the 20^th course held at Sunbury-on-Thames, England, between 10 and 21 August 1981. Ceratium hirundinella is discussed in more detail in the caption to Plate 1. The elongate oblong object in the top right is a diatom referable to the genus Aulacoseira; it is probably Aulacoseira granulata. The scale bar represents 25 µm.

Figure 2. A group of several specimens of Gonyaulacysta dualis from the Upper Jurassic Naknek Formation of Amber Bay, southwest Alaska. This is Stanford University palynology sample PL 5002; the England Finder coordinate is G38/1. The slide was distributed at the 20^th course held at Sunbury-on-Thames, England, between 10 and 21 August 1981. This sample clearly yielded a virtually monospecific assemblage of Gonyaulacysta dualis, which is discussed in more detail in the caption to Plate 15. The scale bar represents 100 µm.

Figure 3. A group of several specimens of Leptodinium mirabile from the Upper Jurassic Naknek Formation of Amber Bay, southwest Alaska. This is Stanford University palynology sample PL 5004; the England Finder coordinate is M40. The slide was distributed at the 29^th course held at Glasgow, Scotland, between 19 and 30 August 1985. Sample PL 5004 produced a palynoflora overwhelmingly dominated by Leptodinium mirabile; rare specimens of Gonyaulacysta dualis are also present. Leptodinium mirabile is discussed in more detail in the caption to Plate 14. The scale bar represents 100 µm.

Bill worked as a field assistant for his geology professor, Mark H. Secrist, during the late summer of 1941. The two of them undertook fieldwork in the central Appalachians and immediately formed an excellent personal and working relationship. These field trips helped Bill to finally decide to major in geology, with a special interest in palaeontology, before the start of his second (sophomore) year in the autumn of 1941. Mark Secrist became Bill's geological mentor and they undertook much joint fieldwork during which they would measure sections, mostly in roadcuts, and collect fossils and rock specimens. Bill's first paper was co-authored with Mark Secrist on the palaeontology of the upper Martinsburg Formation (Ordovician) of Massanutten Mountain in the Shenandoah Valley, Virginia (Secrist & Evitt 1943). In this work, the authors described the Martinsburg Formation and its abundant and diverse macrofauna from two sections, Cub Run and Passage Creek. They described nine new species of molluscs and one new brachiopod variety (Appendix 3; Table 2).

At this time, Bill became especially interested in a study which clearly had great potential for a master’s or PhD project. He had read about a succession of highly fossiliferous Middle Ordovician limestones at Tumbling Run, a small tributary of the North Fork of the Shenandoah River, southwest of Strasburg in Shenandoah County, Virginia. The source of this was a field guide produced for the International Geological Congress in Washington, DC, during 1933, specifically a comment by the bryozoan researcher Ray Bassler that silicified fossils were present at this locality. Unusually, all of the abundant calcareous and organic fossils had been entirely replaced by silica. Tumbling Run was relatively close to home, a three-hour drive away, and Bill visited the locality during the summer of 1941 where he collected many cobble-sized blocks of fossiliferous limestone.

The three-dimensionally preserved trilobites and other fossils could easily and most optimally be extracted by dissolving away the calcareous matrix using hydrochloric acid. However, Bill first etched the limestone blocks with sulphuric acid from old car batteries with their partitions knocked out, in some of the outbuildings at the Old Stone House. The post-acid residues included abundant and superbly preserved silicified bryozoans, ostracods and trilobites. Bill became especially interested in the ostracods and the trilobites. The latter had been previously studied by Reuben J. Ross (Palmer & Dutro 2005) and Harry B. Whittington (Whittington 1941). Bill briefly considered undertaking a master's project at Johns Hopkins on the ostracods from Tumbling Run during the academic year 1942–1943. This did not happen, but by the time he left Johns Hopkins for his wartime service, Bill had decided to pursue a PhD project on the rich collection of silicified trilobites he had already amassed. He had become fascinated by the small size and the glasslike fragility of these exquisitely preserved trilobites, and successfully developed techniques for picking them up and gently releasing them under a binocular stereoscopic microscope. To do this he modified tweezers for extracting the small, delicate trilobite specimens from the washed and dried post-hydrochloric acid residues. Bill extended the tips of the tweezers by attaching a short and very thin strip of aluminium foil to each one with glue. The foil he first used was from the decorative reflective strip within the walls of cellophane drinking straws. The modified tweezers were described in Evitt (1951a) and worked superbly well, due to the flexibility and robustness of the aluminium foil. However, it was clear that he also needed to work on an effective photographic technique. Because the specimens were uncrushed, their three-dimensional nature and irregular shapes ensured that they were not easily oriented for photography and study. Bill did not possess the artistic skills of his mother, so drawing each specimen was not feasible. He needed a photographic technique suited to the great fragility and small size of the trilobites he was studying. Strangely enough, it was the intervention of World War II and Bill's service therein that provided the necessary technique.

Table 2.

A tabulated synopsis of the 11 research papers on macropalaeontology authored by Bill Evitt and his co-workers. Secrist & Evitt (1943) is on the Ordovician shelly faunas of Virginia. The remaining 10 papers are all on silicified trilobites from the Ordovician of the northeast of the United States. Note that all the material studied was from Virginia; however, Evitt (1953) and Evitt & Whittington (1953) included material from New York State and Ohio. All these contributions on trilobites were on material from the Middle Ordovician except Evitt & Whittington (1953), which included specimens from the Upper Ordovician. The numbers of the papers are the ones used in Appendix 3. The three most important papers are indicated with an asterisk. An ellipsis (…) in any of the four columns indicating new taxa means that none of that respective rank were erected.

By early to mid 1941, it was clear that the United States would eventually become embroiled in World War II. Consequently, the demands of national service began to deplete the teaching staff, and courses were quickly modified to include topics suited to wartime, such as meteorology and photogrammetry. After the United States formally entered World War II in early December 1941, Johns Hopkins University, like all American colleges, immediately moved to an accelerated academic schedule. This meant that all courses were concentrated and intensified, and the summer break was eliminated. These accelerated courses did not compromise teaching loads; work was undertaken during the summer, and teaching hours were increased during the terms. Because Bill began his bachelor's course in autumn 1940, he was originally due to graduate in the summer of 1944. The accelerated wartime courses would potentially have Bill graduating in June 1943. However, because of his two summer schools and the more regular courses, he received his bachelor's degree, majoring in geology, during the summer of 1942.

This somewhat unusual transition to graduate-student status was further complicated because Bill had enrolled in the Infantry Reserve Officers Training Corps (ROTC) during his bachelor's programme. By the time of his graduation in the summer of 1942, he still needed to complete two semesters of the full ROTC course. He therefore spent the academic year 1942–1943 as a first-year graduate student taking both graduate and ROTC courses, and beginning research towards his PhD on his silicified Ordovician trilobites.

3.3. Military service during World War II (1943–1946)

By June 1943, the United States had been at war with the Axis for 18 months. Because Bill had completed his ROTC programme in 1942–1943, he had to interrupt his sojourn at Johns Hopkins and join the armed forces in the conflict during June 1943. He joined the Officer Candidate School of the Infantry at Fort Benning in Georgia. Bill became a Second Lieutenant (Infantry) in the US Army during late September 1943, following three months of training comprising class work and strenuous field exercises (Figure 5). The next stage was assignment to a unit which would soon join the European theatre of operations via Fort McClennan, Alabama, in just two weeks time.

During a brief spell of leave following graduation from Fort Benning, Mark Secrist suggested that Bill request a transfer to the US Army Air Force Air Intelligence School (AFAIS) at Harrisburg, Pennsylvania. This was based on the belief that his geological training would be a far better background for a military career in aerial photograph interpretation, as opposed to a posting as a generic infantry officer. A request for a transfer was made to the AFAIS by a close family friend, Colonel Henry Stanwood, who was then the Director of the Maryland Selective Service. Stanwood happened to be married to the youngest daughter of the couple who used to own Bill's first home, on Prospect Circle, Baltimore (subsection 2.1). The AFAIS agreed that Bill’s background in geology was appropriate for work in photogrammetry, but a transfer request from his present unit to join the AFAIS was required. Colonel Henry Stanwood then interceded again and obtained an audience with a General Record, who personally oversaw all military operations in Maryland and adjacent states, in order for Raymond Evitt to present the case for the transfer on behalf of his son. As a result of this meeting, General Record endorsed the application and, following an anxious few days, Bill was assigned to the AFAIS in Harrisburg with a full transfer from the US Army Infantry into the US Army Air Force. Bill always felt profoundly grateful to Colonel Henry Stanwood for facilitating the transfer which probably saved his life. His two contemporaries from the Johns Hopkins ROTC who also became Second Lieutenants (Infantry) in 1943 were both killed in action in Italy within 12 months, aged just 24.

Figure 5.

Bill Evitt proudly wearing his US Army uniform in 1943. The image is reproduced with the approval of the Evitt family.

Bill graduated from the AFAIS in Harrisburg in early December 1943 and, following a brief early Christmas leave, was sent to Seymour Johnson Army Air Force Base in Goldsboro, North Carolina. After Christmas, Bill travelled to another way station, Camp Patrick Henry in Virginia. He eventually boarded a refitted troop ship, The Empress of Scotland, at Newport News, Virginia en route for the Burma-China-India Theatre via Cape Town, South Africa. The Empress of Scotland arrived at Bombay (now Mumbai) after 30 days at sea, and Bill was billeted for one week in barracks at a British military base in the suburb of Worli. The military party then travelled to Calcutta (now Kolkata) by train, and Bill was able to see the famous Deccan Traps large igneous province from his carriage. He was temporarily assigned to the photo intelligence detachment linked to the British headquarters in Calcutta. Bill and his colleagues were now aware that they were ultimately headed for China, and consequently they had no regular duties in Calcutta. In late March 1944, the ‘China Group’ was flown northeast to the United States air base at Chabua in the State of Assam so that they could then fly across the eastern Himalayas (‘The Hump’) to Kunming in Yunnan Province, southern China. By this time, Japanese expansion through Burma towards China and India had been halted, so the flight to Kunming on 30 March 1944 was relatively safe. At Kunming, Bill was posted to the 18^th Photo Intelligence Detachment (PID), a part of the 14^th US Army Air Force, a little under three months after leaving the United States (Figure 6).

The duties of a photo interpreter at Kunming were to examine photographs taken throughout Japaneseoccupied southeastern Asia by the 21^st Photo Reconnaissance Squadron. The principal emphasis was to identify anti-aircraft installations. Several phases of study were performed, depending upon the strategic nature of the materials. In his first few months at Kunming, Bill prepared some simple reports and assisted the report editor. He proofread manuscripts and hence quickly became aware of where the important photographic targets were. Bill returned to photograph interpretation but eventually became responsible for all the reports written by the group (Figure 7).

Bill found the photograph interpretation work fascinating, and discovered that it significantly honed his interpretational and observational skills. Some techniques he learned at Kunming, especially the use of stereoscopy, proved useful in his later work in palaeontology. He used a folding pocket stereoscope to view the aerial photographs in three dimensions. Bill would then prepare a report on any strategically important features. This type of work was clearly relatively similar to examining fossils and describing them. Bill thus could not have obtained more suitable military duties in preparation for a career in micropalaeontology. While Bill was stationed in China, his father and he had corresponded about the trilobite research, particularly photographic aspects. Raymond Evitt sent Bill papers which used stereophotography. This technique was already being used for the study of conodonts (e.g. Branson et al. 1933), and Bill suggested to his father that this technique would be important in his own trilobite research. Bill also undertook some occasional geological exploration of the local area, and located an outcrop of Cambrian strata south of Kunming which yielded abundant trilobites.

Figure 6.

A photograph of Bill Evitt standing immediately outside a village near Kunming in Yunnan Province, southern China, during his posting there in World War II. The image is reproduced with the approval of the Evitt family.

During Bill's early service at Kunming, the principal military focus was repelling the Japanese out of northern Burma and southwestern China in order to reopen the Burma Road. This was achieved, and road transport into China was possible from India. Then the targets became the Japanese presence in eastern and southeastern China (i.e. modern Cambodia, Laos and Vietnam), and Japanese rail and shipping activities. Bill was involved in detailed reports on major cities in this theatre of operations such as Hong Kong, Peking (now Beijing), Saigon (now Ho Chi Minh City) and Shanghai. Life on the base was generally free from direct Japanese military activities; however, there were occasional air raids. During early 1945, Bill and a colleague were sent to Kharagpur, India, to investigate whether radar photography could be applicable to the reconnaissance work of the 18^th PID at Kunming. Their conclusion was that this new technology was not relevant. On the way back, Bill and his partner undertook somewhat impromptu visits to Calcutta and New Delhi in India, and Kandy in Ceylon (now Sri Lanka).

The 18^th PID moved its operational base northwards to new facilities at Peishiyi, west of Chongqing in southwest China, on 7 August 1945. Ironically, while the unit was setting up its equipment, the Second World War came to an abrupt end. So, during mid September 1945, the 18^th PID was disbanded, and received their orders to return home. Bill and his comrades were flown east towards the Chinese coast where they were stationed at Hangchow, southwest of Shanghai, at a former Japanese air base. While waiting to return home, Bill visited tourist venues in and around Shanghai and Peking. The group sailed east from Shanghai aboard an American troop ship on a very stormy passage across the Pacific Ocean. They reached Puget Sound, Washington State, on 29 December 1945. From there the party travelled to nearby Fort Lawton at Tacoma, and then were dispersed homewards. Bill travelled via troop train to Fort Meade, Maryland, where he was met by his parents and rejoined civilian life on 13 January 1946 after nearly 3 years of military service. In recognition of his wartime record, Bill was awarded the Bronze Star medal by the US Army Air Force (Appendix 1).

Figure 7.

A photograph of Bill Evitt deep in thought while typing up a military report on aerial photograph interpretation as part of his duties with the 18th Photo Intelligence Department (PID) in Kunming, southern China, during World War II. The image is reproduced with the approval of the Evitt family.

3.4. PhD research on silicified Ordovician trilo bites (1946–1948)

During early 1946, Bill could relax and reconnect with his interrupted PhD research after his wartime service. His formal return to Johns Hopkins University was due in the autumn of 1946. By his sophomore undergraduate year, Bill had collected sufficient fossil material containing silicified trilobitcs from the Middle Ordovician of Virginia for his PhD research and well beyond (subsection 3.2). He continued his etching of limestone samples and picked and studied the best trilobite specimens. Bill carefully sorted and stored the specimens in glass-covered cardboard slides with wells of sufficient depth. At this time he focussed the scope of his PhD on especially well-preserved material from part of the Tumbling Run section. Entire trilobite fossils proved relatively rare; the faunas are dominated by moult stages which comprise disaggregated cephalons, thoraxes and pygidia (Plates 3,4). Bill physically reconstructed dissociated trilobite sections, which were almost certainly not from the same individual, by carefully gluing them together. This was achieved by uniting the specimens mounted on springy pieces of hair under the stereomicro scope. Typically, a rich sample would yield between 10 and 30 species which meant that working out the affinities of the separate parts, which varied in size due to moulting, was extremely difficult. However, because this material was so rich, it was possible, with much effort, to describe species which were reconstructed at different stages of their life cycles. Juvenile forms could be as small as ∼100 µm in diameter, and the adults could attain lengths of up to 5 cm.

During Bill's wartime service, his father had constructed a suitable camera apparatus and a three-axis stage for orienting the trilobite specimens. The camera was fitted with a long bellows made of interlocking wooden sections between the lens and the film holder. The adjustable bellows allowed different magnifications (up to ∼40×) with good focus and depth of field. The camera apparatus was also designed to allow taking stereopairs of photographs. The use of stereophotography as a tool for the palaeontologist was the topic of Bill's first independently authored paper (Evitt, 1949); he was the first to use stereophotographic techniques in the study of trilobites. Subsequently, Bill described the three-axis stage in Evitt (1951a). The three-axis stage was positioned below the camera lens and held the specimen firmly in its gripping device in any position so that all the trilobite features could be photographed. He used the camera for all of his subsequent work on silicified trilobites. Bill and his students subsequently used stereoscopy (e.g. Helenes 1984, pl. 5), and Bill also used stereo scanning electron photomicrographs in his palynological research (Plate 5; Evitt et al. 1998, pls 7–9).

Plate 3.

Plate 14 of Bill Evitt's PhD thesis on silicified Middle Ordovician trilobites from Virginia, illustrating the (informal) species Calyptaulax micta. This form has never been formalised with this species name. Bill did not use scale bars, and the magnifications quoted below should be considered approximate. The complete specimen in dorsal view illustrated in figure 14a is 16.5 cm long, and its maximum width is 13.0 cm.

Figure 1a–c are of a meraspid at 12× magnification. Figures 2–11 are of cranidia in several orientations and at various magnifications. Figure 12a–d is the cranidium of the (informal) holotype at 4.1×. Figures 13a–b are dorsal and ventral views respectively of a fragmentary cranidium at 4.1×. Figures 14a–d are of various views of an entire individual specimen at 5×. Figures 15–17 are free cheeks at various magnifications. Figures 18–22 are hypostomes and figures 23 and 24 are thoracic segments, all at various magnifications. The image is reproduced with the approval of the Evitt family.

Firstly, a trilobite specimen manipulated with tweezers or an eyelash manipulator was mounted onto the point of an insect pin using water-soluble glue, then whitened with magnesium oxide for photography, before the pin was positioned in the three-axis stage. After photography, the specimen was removed from the pin by dissolving the glue, the coating removed using hydrochloric acid, before being recurated. The extreme dexterity and care needed to manipulate individual dinoflagellate cyst specimens was clearly developed during this stage of Bill's trilobite research. This practical work for the PhD at this time was all done using the extensive outbuildings of the Old Stone House. For example, the cellars made an ideal darkroom.

During the spring of 1946, Bill was invited by Gustav Arthur (‘Gus’) Cooper, the curator in palaeontology at the museum of the Smithsonian Institution in Washington, DC, on a field trip to other localities in the Shenandoah Valley which yield Ordovician silicified trilobites. These fossil localities were discovered during exploration for cement resources in the Second World War. The excursion was principally for Harry B. Whittington (1916–2010), the newly appointed Curator of Palaeontology at Harvard University, Massachusetts. Harry Whittington and Bill became firm friends as a result of their mutual interest in trilobites on this excursion. They did more fieldwork together in the summer of 1946, and this collaboration led to two joint publications (Evitt & Whittington 1953; Whittington & Evitt 1954).

Bill and his father also undertook fieldwork in the Cincinnati area of southwest Ohio to collect fossils from the Upper Ordovician limestone-dominated successions of this region. Unlike the Shenandoah Valley material, this material was not silicified. Later, the father and son team would collect fossils from New York State and eastern Canada. The close participation in their son's professional interests by Raymond and Elsa Evitt showed the strong unity of the Evitt family.

By the autumn of 1946, Bill was ready to return to Johns Hopkins University to formally resume his graduate student career, aiming to obtain his PhD in 1949. He had few remaining course requirements, and was looking forward to spending the next three years largely on research and dissertation writing. A new hire in 1947, Franco Dino Rasetti (1901–2001), was appointed as Bill's research advisor and mentor. Rasetti was an eminent Italian nuclear physicist, and worked in the Department of Physics at Johns Hopkins. He and Enrico Fermi, a Nobel laureate, discovered key processes leading to nuclear fission (Fermi et al. 1934). Interestingly, Rasetti had refused to work on the production of atomic bombs, specifically the Manhattan Project, on moral grounds. Rasetti was a polymath with a photographic memory and had researched other topics, in effect as hobbies, including Cambrian trilobites from the Canadian Rockies (Rasetti 1951), and Alpine wildflowers. Franco Rasetti therefore had the requisite experience to be Bill's mentor, and he was extremely supportive of Bill's work. The two only did a single field trip together, to the southern Appalachians, and Franco allowed Bill to conduct research at his own pace without significant interventions. Eventually Rasetti was the chair at Bill's PhD oral examination in January 1950, and gave a glowing report (Figure 8).

Bill found that life at Johns Hopkins had changed considerably since he had left for his military service. Following World War II, the number of staff in the Department of Geology was reduced due to retirements and the inevitable tragic wartime losses. For example, Mark Secrist and the two previous lecturers in palaeontology had departed. Ernst Cloos, a structural geologist, took over the physical geology course from Mark Secrist. Two new hires in palaeontology were also appointed, neither of whom were trilobite specialists. Furthermore, the chair, Joseph T. Singewald Jr., was rather parsimonious with departmental funds and general resources (Pettijohn 1988). This relative low point in the department's history was reversed by Ernst Cloos following Singewald's retirement, and the former recruited eminent academic geologists such as Francis J. Pettijohn, David M. Raup, Steven M. Stanley and Aaron C. Waters to Johns Hopkins (Pettijohn 1988).

Plate 4.

Plate 15 of Bill Evitt's PhD thesis on silicified Middle Ordovician trilobites from Virginia, illustrating the (informal) species Calyptaulax micta (figures 1–8) and Dolichoharpes reticulata (figures 9–24). Calyptaulax micta has never been formalised. Bill did not use scale bars, and the magnifications quoted below should be considered approximate. However, the dorsoventral width of the single thoracic segment of Dolichoharpes reticulata illustrated in figures 22a–d is 12.5 cm. Figures 1–4 are transitory pygidia, and figures 5–8 are holaspid pygidia of Calyptaulax micta, all at various magnifications. The remaining figures are all of Dolichoharpes reticulata. Figures 9–16 are cephalons in several orientations and at varying magnifications. Figures 17 and 18 are lower lamella of the cephalon at 6×. Figures 19–21 are hypostomes at several magnifications. Figures 22a–d are of a single thoracic segment at 5×. Figures 23a–b are dorsal and ventral views respectively of a transitory pygidium at 12×. Figures 24a–f are all of a single holaspid pygidium in various views, and are all at 5×. The image is reproduced with the approval of the Evitt family.

Plate 5.

A stereopair of two scanning electron microscope (SEM) photographs of the apical region of Protoperidinium sp., a modern thecate dinoflagellate captured with a plankton net from off the California coast. The subovoidal apical pore is prominent, and lies in the centre right of each image. The canal plate lies below the apical pore, but is largely overlapped by the 2′ plate. Each image is 17 µm in width. This plate is Evitt et al. (1998, pl. 9, fig. 7) and is reproduced with the permission of AASP — The Palynological Society.

In addition to his graduate courses and research, Bill was given the post of graduate teaching assistant for the 1946–1947 academic year. These duties entailed being the teaching assistant in the practical classes (laboratories) for the first-year course in physical geology headed by Ernst Cloos. Bill thoroughly enjoyed this work, and it convinced him that his vocation was in earth science research and teaching at a university. However, shortly before the 1947–1948 session began, Bill was asked to visit Ernst Cloos at his home. Cloos was on his sickbed; he had suffered his second heart attack during the week before the autumn semester began. This illness prevented Ernst Cloos from giving the one-semester physical geology course; this represented half of the first-year geology course. Cloos asked Bill to assume full responsibility for all the lectures, practical classes and field trips for this course. Naturally, Bill accepted, but this major task took up most of his time; he had to prepare lectures and, during the course, he was never more than one step ahead of the undergraduates. These relatively onerous duties naturally adversely affected his graduate courses and, especially, his trilobite research. He was only able to seriously continue research work on his PhD during the spring of 1948.

3.5. Farewell to Johns Hopkins University (1948)

In early 1948, J. Edward (‘Ed’) Hoffmeister, a palaeontologist and Johns Hopkins graduate, who was the chairman of the Department of Geology at the University of Rochester, New York, relinquished all teaching duties in order to become dean and concentrate on administration. Ed Hoffmeister contacted Joseph Singewald at Johns Hopkins to ask for suggestions for someone to take over his teaching commitments in palaeontology, sedimentary geology and stratigraphy. Singewald suggested Bill on the basis of his excellence in teaching, and Bill was offered the position at Rochester in the spring of 1948. Bill felt somewhat in a quandary because he had been looking forward to a relatively relaxed final year finishing his trilobite dissertation. His colleagues on the faculty at Johns Hopkins, who greatly admired the Rochester Department, very strongly encouraged Bill to take the job. Perhaps due to a combination of the state of Johns Hopkins immediately post-war, and the lure of a new challenge, Bill accepted this faculty position to start in the autumn of 1948 sight unseen, on the single condition that he was allowed to complete his PhD as soon as possible.

Figure 8.

The very positive report on Bill Evitt's PhD thesis (Trilobites from the Lower Lincolnshire Limestone near Strasburg, Shenandoah County, Virginia) by his principal supervisor, Franco Rasetti of Johns Hopkins University, Maryland. The oral examination upon which the report is based took place in mid-January 1950, with Rasetti as chair. The image is reproduced with the approval of the Evitt family.

Bill had a preliminary visit to the University of Rochester shortly after the end of the spring semester in 1948; he was shown around the campus by Gisela Cloos, a first-year undergraduate. He was much impressed by the Department of Geology, and looked forward to starting work there later that year. Coincidentally Gisela was the daughter of Bill's colleague at Johns Hopkins University, Ernst Cloos. She was also the granddaughter of Hans Spemann, the 1935 Nobel Laureate in Physiology/Medicine and Professor of Biology at the University of Freiburg, Germany (Hamburger 1985). She and Bill clearly got along very well; the couple later married. So it was that Bill left Johns Hopkins University in the summer of 1948 before finishing his PhD dissertation. The PhD was completed at Rochester, and Bill graduated from Johns Hopkins in January 1950 (subsection 4.3).

4.1. Introduction

Bill Evitt embarked on the second leg of his professional journey in the autumn of 1948 when he joined the University of Rochester, on the southern shore of Lake Ontario in western New York State, as an instructor earning a salary of US $3700 per year. At that time the University of Rochester enjoyed a very good reputation, especially in science and medicine; optics and physics were especially strong there. The university was an excellent working environment; the main campus, known as the River Campus, is located 3 km to the south of downtown Rochester on a large bend of the Genesee River. The Rochester years were extremely eventful for Bill in both his personal and professional life. He completed his dissertation, acquired his PhD, established himself as an academic, got married, bought a house and had two sons while there.

4.2. Personal life in Rochester

In Bill's first academic year at Rochester, 1948–1949, he rented rooms in a private home close to the campus. Outside of work, which largely comprised teaching, he explored the Rochester area and beyond. Bill visited many excellent fossiliferous Silurian and Devonian localities in the immediate area, and subsequently took student classes to some of these. He also spent much time with his girlfriend, Gisela Cloos. At the start of the academic session 1949–1950, Bill moved onto the Rochester campus, in the Alpha Delta Phi house as ‘house father’ to the fraternity.

Directly after his dissertation examination in January 1950 (subsection 4.3), Bill plucked up courage to ask Ernst Cloos, who was one member of the panel, for approval to marry his daughter Gisela. Naturally, Cloos did not demur. Their engagement was relatively brief and, on a very hot 29 July 1950, Bill Evitt and Gisela Cloos were married at the Friends Meeting House in Baltimore. They spent their honeymoon in the Appalachians, before moving into 750 University Park, a small apartment in a faculty housing project.

Bill and Gisela had never previously ventured west of the Appalachians, and so they decided to undertake a road trip from Rochester to California and back during the summer of 1951. They converted their Chevrolet two-door sedan into a customised camping vehicle and embarked on a 10,000 km round trip, collecting rock samples on the way. This long and eventful trip took in many states such as Arkansas, California, Idaho, Michigan, Oklahoma, Oregon, South Dakota, Tennessee, Utah and Wyoming. They visited iconic tourist venues such as Crater Lake, Death Valley, Devils Tower, Glacier Lake National Park, the Grand Canyon and Yellowstone National Park. The trip to YoSemite in California had special significance for Gisela. This was because in the early 1930s her father, Ernst Cloos, had spent two summers undertaking geological fieldwork there. This work, along with the rise of Adolf Hitler, persuaded Cloos, who was German, to move permanently to the United States. Bill and Gisela also crossed the Canadian border and visited Ontario on the way back to Rochester.

In November 1952, Bill and Gisela bought their first house in the south of the city of Rochester. This was 36 Midland Avenue, which is a 10-minute drive from the Rochester campus. It was somewhat isolated, being located at the end of a cul-de-sac in a low-lying, swampy area. Bill and Gisela lived in this house for the next four years, and their first two sons, Eric and Steven, were born while they lived there. Eric was born on 17 June 1953, and Steven arrived on 2 December 1955. The Evitts lived in this house very much as a nuclear family, with relatively little contact with the outside world. The two small children and the non-existent public transport made for a strictly limited social life for Bill and Gisela.

4.3. Academic life in Rochester

In 1948, the Department of Geology and Geography at the University of Rochester was very small, with a faculty staff of three geologists and one geographer. Personal relationships within the group were good, and there was a very congenial atmosphere. Bill was the only sedimentary geologist, and taught courses in invertebrate palaeontology, micropalaeontology and stratigraphy to both undergraduates and graduates. Teaching took up most of his time during the student terms. Bill was given excellent laboratory and office facilities at Rochester. He was promoted to assistant professor in 1951 and, during 1955–1956, Bill became associate professor and acting chairman of the department.

At this time, the undergraduate and graduate student body at Rochester largely comprised World War II veterans who were returning to their studies which had been interrupted by the hostilities. These students received significant help with the cost of their studies via the Servicemen's Readjustment Act of 1944 (also known as the ‘GI Bill’). Many of these veterans were near contemporaries of Bill's, and mostly married. Their war-punctuated educations made them ambitious, determined and very mature. This, and the fact that they were the same age as junior instructor Bill Evitt, made for an unparalleled staff-student rapport.

At Rochester the department initially offered only bachelor's and master's degrees, and had only recently been authorised to grant PhDs when Bill joined. The first two graduate students, Donald W. Fisher and Lewis E. Stover, both worked under Bill. Donald Fisher researched the Lower Ordovician palaeontology and stratigraphy of the Mohawk Valley, New York, and graduated in 1952 (Appendix 2; Fisher 1953). Bill advised Donald Fisher, but was not his principal supervisor. Fisher went on to have a distinguished career with the New York Geological Survey (Landing 1994).

In the summer of 1949, Bill resumed his work on trilobites, and spent these months back home at the Old Stone House on his dissertation research. He worked effectively and, by the time he returned to Rochester at the end of the summer, the dissertation was completed and ready for typing. The title was Trilobites from the Lower Lincolnshire Limestone near Strasburg, Shenandoah County, Virginia. After Bill had prepared the dissertation, Johns Hopkins University gave Bill a date in mid-January 1950 for his oral examination. This was during the midwinter break in undergraduate teaching. The examination went very well, the report stating that the dissertation is of ‘exceptionally high quality’ and ‘far above the standards expected from candidates for the degree of Doctor of Philosophy’ (Figure 8). Bill was awarded the PhD on the condition that a version of it would be accepted for publication in a peer-reviewed journal. He prepared part of his PhD dissertation for publication during the early summer of 1950; the manuscript he wrote was later published as Evitt (1951b).

During the autumn of 1953, Lewis Eugene (‘Lew’) Stover (1925–1993) arrived in Rochester. Lew Stover was Bill's first bona fide graduate student, and worked on the diverse and well-preserved Devonian ostracod microfaunas from the highly fossiliferous Windom shale near Rochester, and graduated in 1956 (Appendix 2; Stover 1956). Like Bill, Lew was a married World War II veteran, and the Evitt and Stover families soon became firm friends. Lew Stover later relinquished ostracods to become a leading palynologist and a collaborator of Bill's (Figure 9; Williams & Partridge 1993).

Bill's principal research during his eight years at Rochester was on the silicified trilobite faunas he collected from the Middle Ordovician limestones of Virginia during his undergraduate years at Johns Hopkins University in 1941 – 1942 (section 3). The main focus of Bill’s research on these trilobites was their functional morphology and early ontogeny, and Bill and Gisela worked as a team on this endeavour.

4.4. A husband-and-wife trilobite research team at Rochester

Gisela Evitt (née Cloos) majored in biology as an undergraduate, gaining her bachelor's degree from the University of Rochester in 1950. Following graduation she took a position as a laboratory assistant to Johannes Holtfreter (1901 – 1992), a noted experimental embryologist (Gerhart 1998). Coincidentally Holtfreter was a former student of Hans Spemann, Gisela’s grandfather (subsection 3.5). Not long after they were married, Bill and Gisela attended the annual Geological Society of America (GSA) meeting in Washington, DC, in the autumn of 1950, and visited the Palaeozoic brachiopod expert and museum curator ‘Gus’ Cooper at the Smithsonian Institute National Museum of Natural History there. Gisela in particular was fascinated by the etched silicified brachiopods from the Permian limestones of Glass Mountains in west Texas that Cooper was researching (Cooper & Grant 1972).

Bill had collected samples of these limestones on a field trip associated with the 1949 annual GSA meeting at El Paso, west Texas, and Gisela began to extract these exquisitely preserved brachiopods from the calcareous matrix. Armed with this experience, Gisela started to develop and sort more of Bill's Middle Ordovician silicified trilobites from Virginia. Because Bill was busy teaching students, this work advanced his trilobite research significantly. During 1950–1951, Gisela combined the trilobite work with her day job. However, she became fascinated by the trilobite research, and resigned her paid work with Johannes Holtfreter during 1951 to become Bill's unpaid research assistant. Gisela etched out the trilobite concentrates with hydrochloric acid, sieve-washed them to neutrality and sorted through the post-acid residues. Bill instructed Gisela on how to use a stack of sieves and extract the trilobite fossils from all the fractions that were collected, except the finest fraction. She extracted many superb specimens using Bill's modified tweezers (subsection 3.2; section 8), and one of her many coups was to discover small early ontogenetic stages in the fine fraction which Bill had previously overlooked. Bill thought that the fines would be devoid of fossils of interest, and used to discard this fraction. Therefore it was Gisela’s innate curiosity that led to her discovering these previously unknown juvenile stages. These proved crucial to Bill's interpretations of segmentation changes and the many moults undergone by these fascinating organisms. Initially Bill did not think that these small objects were noteworthy. However, when he realised how common they are, he understood that these ‘baby trilobites’ are extremely significant. Bill acknowledged the massive contribution by Gisela made to his understanding of trilobite ontogeny in Evitt (1961a, p. 987). Also, the species Isotelus giselae was named in recognition of the input by Gisela to this research by Tripp & Evitt (1986).

Figure 9.

Bill Evitt (left) and Lew Stover (1925–1993; right) at the Second International Congress on Palynology at Utrecht, The Netherlands, in August 1966. This image was used in Sarjeant (1998, pl. 5), and is reproduced here with permission.

The silicified trilobites from Virginia are preserved completely undistorted with granular quartz, which gives exquisitely detailed preservation of even the minutest morphological features, both external and internal. The mineralised nature of these fossils makes them easily extractable from the calcareous matrix using hydrochloric acid. The siliceous exoskeletons are all disarticulated, and generally range in size between 1 mm and 3 cm. The assemblages are a mixture of the disarticulated cephalons, pygidia and thoraxes of the protaspid, meraspid and holaspid stages. Therefore, these associations require much careful study to determine precisely which species are present, and the developmental history of each taxon (Plates 3, 4). Bill and his co-authors used stereophotographs of selected specimens to illustrate the complex morphologies.

This work taught Bill the value of concentrating on very-well-preserved fossil material, a paradigm that he religiously adhered to for all his life. He reasoned, eminently logically, that what is readily observable in wellpreserved biotas is of far greater value than the many conjectures necessary with material in an inferior preservational state. Furthermore, Bill believed firmly that if undergraduates are taught with good material, and graduate students research similar assemblages, they will have a good grounding in their subsequent careers when they may be required to work with more poorly preserved associations of fossils. Bill's work on well-preserved silicified trilobites was a new departure in this field, and his modus operandi for both extraction and study was subsequently used by many other researchers.

4.5. The overworked editor (1953–1956)

During his time at Johns Hopkins and Rochester, Bill was an active member of the Paleontological Society. Bill became significantly more involved in 1953, when he was elected to the position of editor of the Journal of Paleontology. He served in this position, and sat on the Paleontological Society council, until he left Rochester in 1956. Bill was elected to take over the editorship from Aldred Scott Warthin, Jr., of the University of Chicago. This well-established journal of the Paleontological Society was first published in 1927 and has always been a highly regarded periodical. The Journal of Paleontology is published bimonthly, and consequently has a significant annual page budget. Naturally, these editorial duties were extremely onerous because Bill was the sole editor. However, this work also kept Bill up to date with modern developments in palaeontology, and provided him with a wide network of valuable contacts throughout the subject. Bill largely edited contributions on what can be termed traditional palaeontology, as befitted this specialist title. However, he handled several papers on relatively new areas at the time such as palaeoecology and statistical methods in taxonomy. Despite this, the tenure of Bill's editorship was well before the advent of paradigm shifts such as molecular methods in palaeontology and the discovery of plate tectonics. Bill edited Hoffmeister et al. (1955a), which was an early classic in palynology. This article demonstrated that Palaeozoic spores extracted by mineral acid digestion could be used for stratigraphical correlation, and Bill surely would not have guessed at this time that his future career would be in palynology. Bill was the last sole editor of the Journal of Paleontology, he relinquished the position in 1956 when he left the University of Rochester. He then became a vice president of the society for 1957. The Journal of Paleontology was then edited by a team of two; in 1956, Bob Kessler and Erwin Stumm jointly took on this important job. This editorial position was the only term of service with portfolio on the board of a learned scientific society that Bill ever undertook. This is perhaps an indication of the all-consuming nature of the duties of a Managing/Technical Editor who also has a full-time day job and a young family. Bill and Gisela's first two sons, Eric and Steven, were both born during Bill's time at Rochester. Indeed, Bill acknowledged that the editorship of the Journal of Paleontology impacted negatively on his research, and probably his teaching too. Despite this, Bill served on the editorial board of Marine Micropaleontology between 1976 and 1982. The only other voluntary committee work that Bill took on, outside his main employment, was membership of the Committee on Fossil Plants between 1970 and 1986, and as a councillor on the board of directors of the American Association of Stratigraphic Palynologists (AASP) in 1971–1972 (Demchuk & Riding 2008, p. 99). Bill was on the scene when the AASP was instigated in 1967, but declined an invitation to be a founding member (Leffingwell 1990).

4.6. Goodbye to Rochester (1956)

In 1955 Bill was promoted to associate professor, and was made acting chairman of the Department of Geology and Geography at Rochester due to the promotion of Ed Hoffmeister to dean. Paradoxically, Hoffmeister's promotion had a negative effect on the department. Hoffmeister had retained the substantive chairmanship; however, he was anxious that he should not be seen to overtly favour his home department within the university as a whole. There was significant overcompensation by Ed Hoffmeister and, as a consequence, the Department of Geology and Geography did not receive its fair share of resources under his tenure as dean. This, together with domestic financial pressures, ultimately triggered Bill's departure from Rochester to the oil industry in 1956 (section 5).

In 1956 Bill had been at the University of Rochester for over seven years, and he was ready for a fresh challenge. General working conditions in the department had deteriorated somewhat, and he was not relishing the role of acting departmental chair. Specifically, departmental budgets were tighter and future prospects were less bright since the halcyon years of the late 1940s and early 1950s. Furthermore, Bill was finding married life with two small children very tough on the salary of a relatively junior academic. The winters in Rochester were cold and long, and Gisela found their house somewhat isolated in that it lacked public transport.

At this time Bill's graduate student, Lew Stover, was nearing the completion of his doctoral research at Rochester and was applying for jobs. One of the positions that Lew was in contention for was an industrial palaeontologist position with the Carter Oil Company in Tulsa, Oklahoma. This was in the palaeontology laboratory headed by William S. (‘Bill’) Hoffmeister (1901 – 1980), a Johns Hopkins University graduate, who was developing a vibrant research programme in palynology (Figure 10). He was also the brother of Ed Hoffmeister. After World War II, the number of micropalaeontologists working in the oil industry increased significantly (Hopping 1967). Lew Stover returned to Rochester from his successful job interview at the Carter Oil Company in January 1956 palpably enthused. The Evitts and the Stovers dined together upon Lew's return from Oklahoma, and Bill Evitt was struck by Lew’s massive enthusiasm about the laboratory in Tulsa. Lew quickly accepted the position after discussing it with Bill Evitt, his mentor. Furthermore, Bill Hoffmeister regularly visited the University of Rochester to present seminars on palynology and its use in geological exploration. These annual seminars were extremely popular with both staff and students because of their acutely topical and applied nature. Lew's enthusiasm and Bill Hoffmeister's charismatic seminars significantly excited Bill Evitt's interest in a job in industry. During a visit by Bill Hoffmeister to Rochester during February 1956, Bill Evitt tentatively inquired as to the possibility of a position with Carter; he and Gisela had previously discussed this scenario. Bill Hoffmeister answered Bill Evitt's question with an impish grin (remember that Bill Evitt then worked for his brother, Ed Hoffmeister), and immediately produced an application form from his pocket. It is clear that Bill Hoffmeister was intending to ask Bill Evitt to apply to Carter on this visit. He later admitted that he had carried the forms with him for a long time waiting for a chance to pass them on to Bill Evitt. Needless to say, Bill Evitt applied, and was soon interviewed. Like Lew Stover, Bill Evitt was very impressed by Bill Hoffmeister's laboratory, the personnel and the work undertaken in Tulsa. Bill Evitt was offered a position as a senior research geologist in Tulsa despite warning his interviewers that he did not care if he ever found a drop of oil! He had no hesitation in accepting the post and immediately tendered his resignation to the University of Rochester.

Figure 10.

A photograph of William S. (‘Bill’) Hoffmeister (1901 – 1980), who became Bill Evitt's mentor in palynology during his time with the Carter Oil Company/the Jersey Production Research Company between 1956 and 1962. This photograph was used in the dedication to Bill Hoffmeister by Bill Evitt in the collection of papers presented at the first Annual Meeting of the AASP held in Baton Rouge, Louisiana, in October 1968, and published as volume 1 of Geoscience and Man in 1970. Reproduced with the permission of AASP — The Palynological Society.

Unfortunately, due to being out of town at the time, Ed Hoffmeister discovered Bill Evitt had resigned from Rochester via the president of the university. Ed Hoffmeister was understandably unhappy to hear this news indirectly, and to lose one of the best members of staff. It is also entirely probable that some of Ed Hoffmeister's dismay at Bill Evitt's imminent departure was exacerbated because he was going to work for his brother, Bill Hoffmeister. The hitherto excellent relationship between Bill Evitt and Ed Hoffmeister was very strained during the months before the former's departure. Ed Hoffmeister tried very hard, but ultimately unsuccessfully, to persuade Bill Evitt to stay at Rochester. Happily, after he ceased to be Dean at Rochester several years later, Ed Hoffmeister rekindled his good relationship with Bill Evitt.

5.1. Introduction

The Evitt family drove west from a comparatively cool Rochester to a sweltering (~45 °C) Tulsa, Okhahoma, in August 1956. They all found the very high Oklahoman temperatures difficult to deal with at first, but gradually acclimatised to the far hotter weather, despite initially living in an apartment with no air conditioning. The family quickly settled in to life in Tulsa, and moved into an air-conditioned home in late 1956. This was 5341 East 26^th Place, which was in a newly built estate (tract) development with a community swimming pool. Bill and Gisela enjoyed landscaping their new garden from what was originally virgin pasture. They also enjoyed the vibrant social life in Tulsa; in the hot Oklahoman summers the swimming pool was a focal point, and good friendships developed quickly. Several of Bill's colleagues at the Carter Oil Company lived in the same development, and he was able to carpool to and from work which was a 20-minute drive away at 1133 North Lewis Avenue in north Tulsa. This left Gisela free to use the family car, which she had been unable to do in Rochester. Bill found the transition from academia to industry both abrupt and gentle in equal measure. As a senior research geologist, his job description was entirely technical with negligible administrative duties. Furthermore, he earned a much more comfortable salary in the private sector, and the whole family received corporate health care benefits. Bill and Gisela's third son, Glenn M. Evitt, was born in Tulsa on 13 September 1958.

5.2. Bill Hoffmeister and the palaeontology laboratory at Carter Oil

The Carter Oil Company was an affiliate of Standard Oil of New Jersey, and undertook all geological research for the parent company. Carter Oil was rebranded as the Jersey Production Research Company in 1959, and Bill Hoffmeister's palaeontology laboratory was separated off within Esso Production Research (now Exxon Mobil). Hoffmeister had worked for many years on foraminifera and petroleum geology for Standard Oil of New Jersey affiliates in the Caribbean and Venezuela (Hoffmeister 1938). He was moved to Tulsa in the early 1950s in order to head a group of micropalaeontologists at the Carter Oil Company, and to develop a corporate capability in stratigraphical palynology.

Hoffmeister was highly ambitious for his team of micropalaeontologists, and provided an extremely amenable and well-resourced working environment for all his staff. Consequently, Bill found the research atmosphere at the Carter/Jersey laboratory exceptionally congenial. Most of the scientific staff had PhDs, and the technicans were also very well trained. It was essentially a scientific (virtually academic) research job with minimal administration and, of course, no teaching or supervision. The mission of the laboratory was to undertake strategic research in micropalaeontology, with the ultimate aim of making the company more effective at finding and producing oil. Only a minor part of the scientists' time was given over to routine service tasks. These, in turn, could be turned into research projects because of the relative youth of the science of micropalaeontology at this time. Within broad limits, the staff at Carter Oil could choose their own research topics. Hoffmeister's palaeontological laboratory at Carter/Jersey was a somewhat similar scenario to the research group headed by Peter Vail at Exxon in Houston, Texas. Vail and his colleagues developed sequence stratigraphy during the 1970s under similar conditions allowing ‘blue-sky research’ (Vail et al. 1977; Haq et al. 1987; Sloss 1988).

Moreover, Hoffmeister enthusiastically encouraged his staff to attend scientific conferences and to publish their findings, provided company approval was forthcoming. He believed firmly that the free flow of information in the rapidly expanding field of micropalaeontology and palynology would benefit all stakeholders, whether they be academics or in industry. Hoffmeister would assuredly have had to use his considerable charisma and significant persistence to persuade the Carter/Jersey management to agree to the virtually pure-research focus of his staff, and their freedom to publish in the mainstream scientific literature and to attend conferences.

There can be no doubt that Hoffmeister was an extremely engaging individual. Bill often recounted numerous anecdotes about Hoffmeister's ability as (what Bill termed) a ‘promoter’. For example, when discribing new methods of palynomorph extraction developed by his laboratory to a group of company executives, Hoffmeister outlined a method that involved producing gunpowder from coal as part of the process. He noted that there was an attendant danger of explosion. As he finished, he said, ‘Of course you lose a few technicians along the way, but the spore and pollen recovery is excellent!’ Apparently he said this with such a totally impassive face that it took some of his audience a significant time to be sure that he was joking (personal communication, Bill Evitt to JL-C).

5.3. The history and role of palynology in the Carter Oil Company

Bill Hoffmeister was very impressed by the consulting work on palynology undertaken in South America for Standard Oil of New Jersey by Robert S. Tschudy, and research by Shell and their affiliates in the Orinoco Delta in eastern Venezuela (Muller 1959). On this basis, Hoffmeister suggested to the Carter Oil Company management that the company should instigate a programme in palynology themselves. Hoffmeister was a very persuasive man, and this was agreed. The eminent pollen/spore expert Leonard R. Wilson, then of the University of Massachusetts, Amherst, Massachusetts, was employed as an external consultant to assist Hoffmeister.

The first team of palynologists at Carter Oil in the early 1950s were Bill Hoffmeister, Raymond E. Malloy, Frank L. Staplin and Leonard R. Wilson. In the summer of 1956, when Bill Evitt arrived in Tulsa, Ray Malloy had already left Oklahoma to work in Peru, and Frank Staplin was about to join Imperial Oil in Calgary, Canada. So the Tulsa team of palynologists from mid-1956 comprised Bill Evitt, John W. Funkhouser, Bill Hoffmeister, Lew Stover and Leonard R. Wilson. Then, in the late 1950s, Harry A. Leffingwell joined the team.

John Funkhouser's research background was in biology, specifically South American frogs. Funkhouser undertook graduate research at Stanford University in California, and was mentored in palynology by Hans Thalmann, an expert on foraminifera. Thalmann had perceptively realised how significantly industrial palynology was going to expand in the future, and had established a small palynology processing laboratory at Stanford University. After John Funkhouser graduated, it was Hans Thalmann who suggested that he should apply for a job with the Carter Oil Company. The fact that a researcher on modern frogs was accepted into an industrial micropalaeontology unit is an indication of how few appropriately trained palynologists were around in the mid 1950s. Lew Stover, of course, was an expert in Devonian ostracods; his only experience of palynology at that time was the occasional seminars given by Bill Hoffmeister at the University of Rochester. Also present in the group was Lili Ronai, a specialist on foraminifera who trained at the American Museum of Natural History in New York under Brooks Ellis.

The Carter Oil Company palynology group investigated the palynomorph content of samples from prospects and fields owned and operated by Standard Oil of New Jersey. Prior to Bill Evitt and Lew Stover's arrival in Tulsa in 1956, Bill Hoffmeister worked mainly with Ray Malloy and Frank Staplin. This three-man team confirmed that palynomorphs were indeed excellent stratigrapical index fossils. This conclusion was simultaneously being drawn elsewhere in the United States (Woods 1955a, 1955b; Wilson 1956, 1961; Grayson 1960). Additionally, Isabel C. Cookson and her collaborators were investigating stratigraphical palynology in Australia at this time (e.g. Cookson 1953, 1954; Baker & Cookson 1955) and several practitioners were active in Europe (e.g. Balme & Butterworth 1952; Butterworth & Millot 1955; Downie 1957; Gocht 1952, 1955, 1957, 1959; Eisenack 1958; Hughes 1958; Sarjeant 1959).

The first publications on palynology from the Carter Oil laboratory included Wilson & Hoffmeister (1953, 1955, 1956), Hoffmeister & Staplin (1955) and Hoffmeister et al. (1955a, 1955b). Hoffmeister et al. (1955a) is a classic, and documented Upper Palaeozoic spores from the subsurface of Oklahoma. This was one of the first contributions on stratigraphical palynology directly applicable to industrial operations. Bill Evitt suspected that Hoffmeister et al. (1955a) was issued relatively quickly due to a perceived rivalry with stratigraphical palynologists at Shell such as Jan Muller (Kuyl et al. 1955). The data presented in Hoffmeister et al. (1955a) were relatively old, and not considered to be commercially sensitive by the management of the Carter Oil Company. Despite this, Bill Hoffmeister would have had to argue hard for permission to publish. Other relevant publications include Hoffmeister (1959, 1960).

5.4. A new era: the industrial use of marine palynomorphs

During the 1950s, pollen and spores were beginning to be used in oilfield operations, but knowledge on, and the use of, the various marine palynomorph groups was minimal. One of the aims of Bill Hoffmeister's team was to undertake both routine service requests from affiliates in the Esso group of companies, and applied research into both marine and terrestrial palynology. The research into the biostratigraphical utility of aquatic palynomorphs undertaken by Hoffmeister's group in Tulsa was truly groundbreaking. Very little was known about organic-walled marine microplankton at this time. It is clear that Hoffmeister was aware of the stratigraphical potential of fossil dinoflagellates and other aquatic palynomorphs prior to Bill Evitt's recruitment (Wilson & Hoffmeister 1953, 1955). The latter was especially significant in terms of the development of aquatic palynology. Wilson & Hoffmeister (1955) briefly described their study of the hystrichospheres from around 1000 Palaeozoic to Cenozoic samples. They recorded 16 or 17 genera, and noted that certain forms have restricted stratigraphical ranges and that hystrichospheres are proxies for marine conditions.

Others were also realising the value of aquatic palynomorphs. For example, Raymond D. Woods of the Humble Oil and Refining Company in Houston, Texas, briefly mentioned dinoflagellates and hystrichosphaerids, and illustrated three specimens (Woods 1955a, p. 371, pl. 1, figs 3, 6). The same author also wrote: ‘In addition, current research on spores and pollen has revealed the distribution of heretofore little known microfossils, particularly the “hystrichs” which are proving to be as useful as plant remains in stratigraphic work' (Woods 1955b, p. 135).

The expertise of Bill Hoffmeister and Leonard Wilson was principally in pollen and spores, and Hoffmeister plainly needed someone else to undertake research into marine palynomorphs at this time. Thus, when Bill Evitt joined the Carter Oil Company in 1956, the research portfolio on marine palynology begun so competently and far-sightedly by Hoffmeister and Leonard Wilson in the early 1950s was passed to him in its entirety under the project title of ‘little known microfossils’. Bill Evitt therefore already had an excellent sample base, together with Hoffmeister and Wilson's initial observations.

After the first few weeks of corporate familiarisation at Carter, Bill Evitt quickly realised that his new job offered the exciting opportunity to be at the forefront of an entirely new field in the modern era of palynology, i.e. the study of fossil dinoflagellates, hystrichospheres and related marine microplankton. Prior to starting his new job, he had no practical experience in palynology. Despite this, the procedures of extraction using mineral acids, and the concentration, examination and identification of palynomorphs were similar in principle to his previous work with trilobites at Johns Hopkins and Rochester universities. The main new aspects of palynology, apart from the unfamiliar fossil groups, were the use of hydrofluoric acid and becoming familiar with the prolonged use of a biological microscope. In addition to routine service work, Bill Evitt was specifically instructed by Bill Hoffmeister to investigate marine palynomorphs of strategically important successions with a view to using them as index fossils, and was given a great deal of freedom and independence in this endeavour. This degree of latitude in a research role was (and still is) extremely unusual in the oil industry.

Plate 6.

A montage of dinoflagellate cysts which were of special interest to Bill Evitt.

Figures 1–3. Nannoceratopsis gracilis. All specimens from the lowermost Middle Jurassic Brent Group (probably the Broom Formation) from quadrant 211 in the northern North Sea (precise well/depth details unknown). Note that the specimens are all in left lateral view, with the prominent dorsal antapical horn to the right-hand side. The autophragm is microreticulate, and the small cingular archaeopyle can be discerned close to the apex on all three specimens (Piel & Evitt 1980a). 1. British Geological Survey (BGS) specimen number MPK 14583, slide 0004, England Finder coordinate T38/3 (length 60 µm; width 47 µm). 2. BGS specimen number MPK 14584, slide 0004, England Finder coordinate W51 (length 58 µm; width 47 µm). 3. BGS specimen number MPK 14585, slide 0004, England Finder coordinate P41 (length 67 µm; width 44 µm). The scale bars all represent 25 µm.

Figure 4. Gillinia hymenophora. The holotype from the Rough Range South No. 1 bore, Western Australia, from between 729.39 and 728.47 m (Cookson & Eisenack 1960, pl. 3, fig. 4). Gillinia is a Late Cretaceous genus with a global distribution and Gillinia hymenophora is marker for the Santonian to Campanian—Maastrichtian interval in Australia (Helby et al. 1987, fig. 40). It is partiform and a representative of the Phanerodinium complex of Evitt (1985). Note the cingulum which is located high on the cyst, and with pericoel locally developed in the lateral cingular areas. The length of the specimen is 38 µm, and its width is 33 µm; the scale bar represents 25 µm.

Figures 5, 6. Dinogymnium undulosum. The holotype from the Upper Cretaceous Madura Shale from 295.05 to 293.52 m in the Madura No. 1 Bore (Cookson & Eisenack 1970, pl. 10, fig. 3). This water borehole was drilled in the Eucla Basin, Western Australia (Lowry 1968). Note the broad, rounded apices, the prominent cingulum and sulcus, the subequal epitract and hypotract, and the undulating longitudinal ridges. Herngreen (1975, p. 63) suggested that Dinogymnium denticulatum may possibly be synonymous with this species. The length of the specimen is c. 64 µm, and its width is 34 µm; the scale bar represents 25 µm.

Figure 7. Palaeoperidinium pyrophorum from the earliest Paleocene (Danian) Sobral Formation of central Seymour Island, Antarctica. British Antarctic Survey slide number D9.129.1A, England Finder coordinate K65/1. Photomicrograph taken by Dr Vanessa C. Bowman (British Antarctic Survey) and is used with permission. The specimen is in dorsal view. Note the subpentagonal outline, the three relatively short, distally pointed polar horns, the prominent cingulum and the two cyst layers; the innermost one is the apparently closely appressed endophragm and periphragm. The outer layer is the smooth exophragm (Evitt et al. 1998). The scale bar represents 25 µm. This specimen was originally illustrated in Bowman et al. (2016, fig. 3.4).

Figure 8. Dinogymnium nelsonense. The holotype from the Upper Cretaceous at 1899.82 m in the Nelson Bore (Cookson 1956, pl. 1, fig. 10). This borehole was drilled by the Victoria Department of Mines close to a bridge over the Glenelg River at Nelson, Glenelg Parish, southwest Victoria, Australia (Deflandre & Cookson 1955, fig. 1). Note the elongate ambitus, the truncated apical region, the prominent cingulum, the large epitract and the relatively thin, smooth wall which exhibits longitudinal folds. The length of the specimen is 70 µm, and its width is 38 µm; the scale bar represents 25 µm.

Figure 9. Dinogymnium westralium. The holotype from the Upper Cretaceous (Campanian—Lower Maastrichtian) Korojon Calcarenite between 423.06 m and 420.62 m in Wapet's Rough Range Well No. 4 (Cookson & Eisenack 1958, pl. 1, fig. 9). This well is located in the Exmouth Gulf area of the Carnarvon Basin, Western Australia. Note the elongate biconical ambitus, the relatively narrow cingulum and the dense longitudinal ridges which have irregular distal margins. The hypotract is slightly larger than the epitract, and has a broadly rounded antapex. The length is 47 µm, and the width is 28 µm; the scale bar represents 25 µm.

Bill Evitt's first project was to prepare and study palynomorphs from the highly macrofossiliferous Silurian and Devonian strata of western New York State. Bill Hoffmeister had asked Bill Evitt to sample this succession before his arrival in Tulsa. Bill Evitt firstly learned how to prepare this material and produce strew-mounted slides, before studying and photographing the palynomorphs. When Bill Evitt arrived in Tulsa, palynomorph processing procedures were, at best, rudimentary. Consequently, Bill Evitt, John Funkhouser and their laboratory technicians worked on improving techniques for the extraction, concentration and presentation of palynomorphs from sediments and sedimentary rocks. This work was written up as Funkhouser & Evitt (1959). This paper includes sections on gravity separation using zinc chloride solution, the use of water-soluble mountants and ‘swirling’ using a large watchglass to separate palynomorphs from organic particles of slightly higher density (Appendix 3). Bill and John Funkhouser were among the first to document techniques such as heavy liquid separation and ‘swirling’ for the concentration of palynomorphs. Unfortunately, Bill Evitt found that the majority of his Silurian and Devonian samples from New York State produced only sparse and poorly preserved palynofloras. However, part of the Middle Silurian Maplewood Shale yielded abundant and well-preserved acritarchs, or hystrichospheres, as these palynomorphs were then known.

The next investigation was to prove much more rewarding for Bill Evitt. An Esso affliliate in Pakistan, the Socony Vacuum Oil Company, requested the biostratigraphical analysis of some subsurface samples of ‘Mid’ to Late Cretaceous age, from which he recovered some abundant palynofloras which included many unequivocal fossil dinoflagellates. Bill soon realised that the latter were largely taxonomically undescribed, but they offered significantly greater stratigraphical potential than did the much more thoroughly researched pollen and spores. This was Bill's first research success in palynology, but it has never been published. It was studying this material that convinced Bill that much of the dinoflagellate record was represented by the cyst phase of the life cycle. At this time it was simply assumed that the dinoflagellate fossil record represented preserved motile dinoflagellate thecae. Except for the fact that the delicate cellulosic nature of the dinoflagellate theca is extremely unlikely to be preserved, this was entirely understandable because some fossil taxa are extremely similar in morphology, shape and size to living dinoflagellates. For example, the Late Cretaceous to Paleocene species Palaeoperidinium pyrophorum (Plate 6, figure 7) is similar in morphology to modern Protoperidinium thecae except that the wall relief in the former is interior and not exterior (see A3.63 below).

Plate 7.

Six of the 35-mm transparency slides included in the ringbound file of course materials that Bill Evitt provided to participants of the two-week Teaching Conferences on Fossil Dinoflagellates (section 10). These slides accompanied the practical exercises and the specimens for study. These four specimens are all skolochorate forms with apical archaeopyles. All of the images are reproduced with the approval of the Evitt family.

Figures 1, 2. Hystrichokolpoma sp. cf. H. cinctum; ventral view, high and low focus respectively; Calvert Formation, Miocene, Maryland. Note these photographs have been image-reversed or inverted. This was illustrated as Hystrichokolpoma sp. in the course manual as slides 16 and 17. Note the funnel-shaped intratabular processes which narrow distally. Proximally, these distinctive processes approximate to the area of their respective plate and are open distally. The antapical (1″″) process is by far the longest. By contrast, the cingular and sulcal processes are the most slender. A standard, presumably sexiform, gonyaulacacean tabulation is clearly indicated by the processes, and the ventral organisation is L-type. It is not considered to be Hystrichokolpoma cinctum sensu stricto due to the relatively entire distal margins of the processes. In the type material, these are significantly scalloped (Williams & Downie 1966, fig. 46; Damassa 1979a, fig. 5). This morphotype is also similar to Hystrichokolpoma rigaudiae; however, Hystrichokolpoma sp. cf. H. cinctum is significantly larger and the processes are larger and taper distally. The processes in Hystrichokolpoma rigaudiae are expanded and slightly furcate distally (Deflandre & Cookson 1955, fig. 42). The cyst body is 50 µm in length, and is 60 µm wide; the overall dimensions of this specimen (including processes) are 110 µm long by 80 µm wide.

Figures 3, 4. Hystrichosphaeridium tubiferum; ventral view, high and low focus respectively; Fox Hills Formation, Maastrichtian, Montana. These were slides 10 and 11. This is a classic chorate gonyaulacacean dinoflagellate cyst with plate-centred processes, and it was among the species which first convinced Bill Evitt that most of the Mesozoic and Cenozoic hystrichospheres were dinoflagellate cysts (sections 5, 6, 9; Figure 11). Specifically, it is clear that the processes have a one-to-one relationship to the thecal plates. Furthermore, in some cases, the polygonal outlines of the process tips indicate the shape of the respective thecal plate. For example, see the distinctly quadrangular middorsal postcingular plate (4″′) in figure 4, which mimics the overall outline of this plate in the parent theca. Other obvious examples of this are the elongate outlines of the distal tips of the cingular processes in figure 4. Like in Hystrichokolpoma sp. cf. H. cinctum above, the intratabular processes reflect a standard, gonyaulacacean tabulation pattern and exhibit L-type ventral organisation. The sulcal processes, the L-type ventral configuration and the intersection of the sulcus and cingulum are clearly evident in figure 3. The apical archaeopyle has operated, and the precingular, cingular, postcingular and antapical plates are shown beautifully in figure 4. Note also the relatively smooth cyst wall and the prominent hollow, trumpet-shaped processes which are open distally but do not communicate with the cyst body proximally. This is because the processes in the centre of each plate are formed of periphragm, which only separates from the endophragm at the base. In the areas between the processes, both cyst layers are closely appressed. The cyst body is 44 µm in length, and is 40 µm wide; the overall dimensions of this specimen (including the processes) are 64 µm long by 88 µm wide.

Figure 5. Perisseiasphaeridium pannosum; oblique ventral view, low focus; Lower Cretaceous (Barremian), The Netherlands. This was slide 18, and Bill termed it Perisseiasphaeridium sp. This genus is low in diversity and ranges from the Late Jurassic to the Early Cretaceous (Fensome & Williams 2004, p. 515–516). It is especially characteristic of the latest Jurassic—earliest Cretaceous interval (Davey 1982; Nøhr-Hansen 1986; Stevens & Helby 1987; Riding & Thomas 1988). The holotype is Eocene, but this material was reworked from the Late Jurassic (Kimmmeridgian) (Fensome 1979; Riding 1987). Perisseiasphaeridium is a chorate genus with prominent plate-centred processes in the large plate areas such as the precingulars and postcingulars which are distally expanded, hollow, multifurcate and open. By contrast, the cingulum and sulcus bear slender, solid processes. Note the apical archaeopyle, the smooth autophragm and the complex distal branching exhibited by the large processes. This focal level is on the dorsal side and the 2″, 3″, 4″, 3c, 4c, 3″′, 4″′, 5″′ and 1″″ processes can all be clearly discerned. The cyst body is 70 µm long, and 80 µm in width; the overall dimensions of the specimen (including the processes) are 125 µm long by 140 µm wide.

Figure 6. Oligosphaeridium sp. cf. O. pulcherrimum; ventral view, high focus; Mowry Shale, Lower Cretaceous (Albian), South Dakota. This was slide 14, and Bill termed it Oligosphaeridium sp. Oligosphaeridium is a very diverse chorate dinoflagellate cyst genus which is most characteristic of the Cretaceous, but ranges from the Late Jurassic to the Palaeocene (Wilson & Clowes 1980, p. 74; Fensome & Williams 2004, p. 470–475). It was most abundant during the Early Cretaceous, where the most common representative was the type, Oligosphaeridium complex (see Morgan 1980; Heilmann-Clausen 1987). The prominent process-free equatorial area is the most diagnostic feature of Oligosphaeridium. Indeed, the genus is identical to Perisseiasphaeridium except for the complete lack of cingular and sulcal processes. Note the apical archaeopyle, the smooth cyst wall and the intricate branching at the distal part of the plate-centred processes. Branching occurs in the distal 35 to 25% of the processes. The extreme distal parts of the branches tend to be connected by thin, smooth trabeculae. The processes are distally flared, hollow and open distally. The anterior sulcal (as) plate is clearly seen at the top of the sulcus; this is termed the sulcal tab. The separation of periphragm (the processes) from the underlying endophragm can be seen at the proximal part of the processes. The latter phenomenon is best observed on the large antapical (1″″) process. The intricate branching in the distal part of the processes suggests a strong affinity with Oligosphaeridium pulcherrimum. This species is similar in size to the South Dakotan material, and both are Albian in age. The distal branching is significantly greater than in Oligosphaeridium complex. However, the type material of Oligosphaeridium pulcherrimum lacks the trabeculae which connect the distal process branches of the form illustrated here (Deflandre & Cookson 1955, figs 21, 22). The cyst body is 63 µm long, and 60 µm in width; the overall diameter, i.e. including the processes, is 125 µm.

Figure 11.

A line drawing to illustrate the derivation of a typical chorate dinoflagellate cyst. This is the Late Cretaceous to Eocene (Turonian—Ypresian) chorate species Hystrichosphaeridium tubiferum based on material from the Upper Cretaceous (Maastrichtian) Redbank Formation of New Jersey. The figure seeks to illlustrate its relationship with the parent dinoflagellate thecate cell. A, the thecate cell which exhibits a standard L-type sexiform gonyaulacacean tabulation pattern in ventral view. B, the Hystrichosphaeridium tubiferum cyst within this thecate cell; note how the expanded distal extremity of every cylindrical platecentred process is adherent to the inside of the central part of each thecal plate. C, the isolated Hystrichosphaeridium tubiferum cyst when the thecate cell has fully disintegrated and dispersed. The cyst body is shaded. The overall diameter of Hystrichosphaeridium tubiferum including processes varies between ca. 60 and 80 µm, and is typically around 75 µm. Parts B and C of this iconic diagram were originally published in Evitt (1963a, fig. 3); this figure is adapted from Evitt (1963a, fig. 3), Evitt (1985, fig. 3.3) and Fensome et al. (1996, fig. 26).

At the same time, Bill also hypothesised that many Mesozoic and Cenozoic hystrichospheres were in fact dinoflagellate cysts. This theory had been pondered earlier by the European researchers Wetzel (1933a, 1933b), Deflandre (1936a, 1937) and Lejeune (1937). Genera such as Hystrichosphaera (now Spiniferites) and Hystrichosphaeridium shaped Bill's theory. He noticed that (i) the processes on genera such as Hystrichosphaeridium apparently emerged from the centre of plates in the standard gonyaulacacean tabulation pattern, and (ii) the distal part of these processes in all of these process-bearing forms must have been originally in contact with the inside of the dinoflagellate thecal wall (Figure 11; Plates 7–11). The key evidence for the former phenomenon was the fact that some processbearing (chorate) dinoflagellate cysts exhibit expanded process tips which are polygonal in outline, and that these features are precisely the shape of the thecal plates in their respective positions. These observations gave rise to the now-famous diagram of a specimen of Hystrichosphaeridium tubiferum (Plate 7, figures 3, 4) inside a hypothetical motile theca (Figure 11). This line drawing illustrating the relationship between the dinoflagellates and the hystrichospheres has become an icon of dinoflagellate cyst literature, and was first published in Evitt (1963a, fig. 3). Bill, of course, was an accomplished microscopist by this time and this, together with his highly tuned observational skills of small-scale features, allowed him to undertake the three-dimensional reconstruction of the spiny cyst inside a theca. This was based on studying well-preserved fossil chorate dinoflagellates at several focal levels. Naturally, the fact that Bill could convincingly demonstrate that chorate dinoflagellate cysts formed inside another body (presumably the theca) also helped to demonstrate that the vast majority of proximate and proximochorate fossil dinoflagellates represent the cyst stage. From this point on, as Bill examined more and more material, he realised that there is a complete gradation between proximate, proximochorate and chorate dinoflagellate cysts (Figure 12).

Figure 12.

A diagram to illustrate the range of ornamentation exhibited by dinoflagellate cysts in terms of relative height. The continuum between low relief features on the left and the relatively long processes on the right is subdivided into three types of dinoflagellate cysts (i.e. proximate, proximochorate and chorate) depending on the ornamentation length as a percentage of the shortest diameter of the central body. The image is adapted from Fensome et al. (1996c, fig. 22), which was in turn modified from Sarjeant (1982a, fig. 2).

Bill first presented his new ideas outside the Carter Oil Company group in a lecture to members of the Paleobotanical Section of the Botanical Society of America, who visited Tulsa on a field trip during their annual national meeting in Oklahoma City in 1958. Clearly, the project on the Cretaceous of Pakistan first excited Bill's great interest in the dinoflagellates, especially their complex morphologies. His skills in analysing morphology had already been honed by his trilobite research and his aerial photography in the US Army Air Force.

Bill Evitt authored or co-authored six papers while employed by Carter/Jersey (Appendix 3), all of which were issued with the enthusiastic encouragement of Bill Hoffmeister. In addition to these contributions, Bill Evitt and his colleagues prepared an alphabetically arranged card index file with each fossil dinoflagellate genus and species having a card with illustrations and its published description (Riding et al. 2012). This card index would help the Carter/ Jersey palynologists familiarise themselves with the known taxa, and identify them. When Bill Evitt left Jersey for Stanford in 1962, the index had grown to around 1000 cards, and he was allowed to take the original index with him to Stanford, leaving a copy in Tulsa.

5.5. Doing Europe — 1959

5.5.1. Background

Bill Evitt was very well regarded at Jersey Production Research, and he was promoted to research associate in 1959. Furthermore, during spring 1959, Bill Hoffmeister and his line manager told Bill Evitt that the laboratory had some unspent travel funds in the budget, and they asked him if he would like to utilise this to further develop his expertise in the use of fossil dinoflagellates in petroleum exploration. This, of course, was a fantastic opportunity and Bill Evitt immediately suggested an extended visit to Europe in order to work with the two pioneers of marine palynology, namely Georges Deflandre of Paris, France, and Alfred Eisenack from Tübingen, Germany (Figures 13, 14). This was readily agreed, and Bill embarked on a two-month working visit in August 1959 to be mentored by Deflandre and Eisenack, to work on their extensive collections, and discuss his new ideas on dinoflagellate life cycles and the affinity of the hystrichospheres. These hypotheses were both somewhat preliminary in 1959, entirely unpublished and significantly at variance with the interpretations of both Deflandre and Eisenack. However, Bill's primary mission was to learn all he could from these giants of the subject, who had produced the vast majority of the literature on fossil dinoflagellates at that time (e.g. Deflandre 1935, 1936a 1936b, 1937, 1938, 1941; Eisenack 1935, 1936a, 1936b, 1938a, 1954, 1958; Deflandre & Cookson 1955).

Both Georges Deflandre and Alfred Eisenack were very happy to host Bill, and they duly received him into their respective workplaces with great courtesy; the trip to Europe was a resounding success. It led to lifelong friendships between Bill and these eminent early researchers, who were profoundly different in many respects. Bill corresponded extensively with both Deflandre and Eisenack over many years, and he developed a massive respect for their major contributions to our science. The dedication in Evitt (1985, p. iii) is to both Deflandre and Eisenack.

During August 1959, Bill and Gisela sailed from New York to Southampton on the USS United States. Both sets of parents had agreed to care for the three boys for the duration of the European tour. Gisela's mother looked after the infant Glenn; she was especially keen that her daughter had a chance to reconnect with her German relatives. Raymond and Elsa Evitt cared for Eric and Steven, who were six and four respectively at the time. This was the first time Bill had visited Europe, and it was Gisela's first trip there since World War II.

After a few days in London, the couple took a train north to Sheffield so that Bill could briefly visit Charles Downie and his then-postgraduate student William A. S. (‘Bill’) Sarjeant at the University of Sheffield. Bill presented his new ideas on the nature of the dinoflagellate fossil record, the affinity of some of the younger hystrichospheres and the archaeopyle to Downie and Sarjeant. Initially, the two Sheffield palynologists were somewhat negative and sceptical (Sarjeant 1976, p. 1 –2). The visit to the University of Sheffield was unexpected, and Sarjeant (1984a, p. 4) somewhat amusingly recalled that, at the time, Charles Downie and he thought that Bill was a crank! It was only when his first papers on fossil dinoflagellates were published, two years later (Evitt 1961b, 1961c, 1961d), that Downie and Sarjeant realised just how perceptive Bill's ideas were. Despite this uncertain start, Bill clearly struck up a good working relationship with the two Sheffield palynologists because they subsequently published together on the classification of the acritarchs and the nature of fossil dinoflagellates (Downie et al. 1963). Following Downie et al. (1963), Bill never worked closely with Downie again. By contrast, he maintained a close relationship with Bill Sarjeant, largely via correspondence. However, Evitt and Sarjeant never published together after Downie et al. (1963). Incidentally, Bill and Gisela did not especially warm to the city of Sheffield during their short visit there, and opted for Chinese meals as opposed to the local fare. What they undoubtedly noticed was the long and painful recovery from World War II, which was especially protracted in the northern cities of England. Because it was (and still is) an industrial centre, specialising in steelmaking, Sheffield had suffered terrible bombing during the conflict (License 2000).

Figure 13.

A photograph of the French algologist and micropalaeontologist Georges Deflandre (1897–1973) at his desk in the Laboratoire de Micropaléontologie at the École Pratique des Hautes Études, Paris, France. The image is reproduced with the permission of AASP — The Palynological Society.

From Sheffield, Bill and Gisela returned to London before travelling to Hamburg in northern Germany by train and ferry. In Hamburg they met Gisela's sister, Veronica, who was then a student. The three of them hired a car and took a two-week vacation before Bill was due in Tübingen to begin working with Alfred Eisenack. The intention was to drive southwest to Freiburg and visit Gisela's family there. At that time, Gisela's grandmother still lived in the house built by her husband, Nobel Laureate Hans Spemann, and in which Gisela had been born. Gisela had not seen her grandmother for 21 years. Unfortunately the Evitts' arrival in Freiburg coincided with the death of Gisela's aunt, and they went to Lake Constance in Switzerland for the funeral. Gisela and Bill's longstanding interest in textiles began in Switzerland, where they visited the annual exhibition of a weaving school. Bill and Gisela fell in love with Freiburg and the Black Forest, and undertook many visits to the extended family. These included Gisela's godmother, Rose ten Bruggencate, and Neisa, her 18-year-old daughter. Neisa was about to finish her final secondary-school exams (Abitur). Because Neisa wished to travel, it was agreed that she would travel to Tulsa the next year, 1960, where she would study English and help out with the three Evitt boys.

Figure 14.

A photograph of the eminent German marine palynologist Alfred Eisenack (1891 – 1982). Alfred worked at the University of Tübingen, and lived in nearby Reutlingen in southwest Germany. Eisenack is pictured here in Tübingen during 1963. This image was used in Sarjeant (1998, pl. 5), and is reproduced here with permission.

5.5.2. Visiting Alfred Eisenack in Tübingen

Bill and Gisela travelled northeast to Tübingen during late September 1959. Tübingen is an old university town in Baden-Württemberg, southwest Germany, and the couple stayed in a small hotel near this famous seat of learning. Gisela explored the ancient city, and the surrounding area, while Bill worked with Alfred Eisenack in his laboratory at the University of Tübingen. Alfred Eisenack (1891 – 1982) had trained in geology, but his career was tragically interrupted by both world wars. He became a schoolteacher in Königsberg (now Kaliningrad) and eventually fulfilled his lifetime ambition of becoming a university researcher in 1951, when he was 60 years old (Gocht & Sarjeant 1983; Sarjeant 1985; Evitt 2001). He retired in 1957, so when Bill visited in September 1959, Eisenack had no teaching duties.

Alfred Eisenack's first studies in palynology were on blocks of allochthonous Ordovician, Silurian and Jurassic limestones derived from the Baltic Sea in glacial erratics found on the North German Plain (e.g. Eisenack 1931). He moved on, for example, to studies of indigenous Cretaceous and Palaeogene material, including many collaborative studies with Isabel Cookson on material from Australasia (Gocht 1982; Riding & Dettmann 2013). The first of these southern-hemisphere studies was the classic Cookson & Eisenack (1958).

Eisenack was a courteous, generous and welcoming individual, and he made Bill very comfortable throughout his extended stay in Tübingen. Bill was able to examine any slides in his extensive collections that he wished. For example, Eisenack had much wellpreserved Cretaceous and Palaeogene material from Germany. Alfred Eisenack had discovered superbly preserved fossil dinoflagellates from Eocene phosphatic nodules from Samland in Kaliningrad Oblast (Eisenack 1938a), and it seems likely that he advised Bill at this time about how early diagenetic concretions/nodules can frequently yield superbly preserved palynomorphs. Bill also studied the type material of the important chorate dinoflagellate cyst species Areosphaeridium diktyoplokum during this visit (Evitt 1972).

Bill found that the specimens he studied in Germany confirmed his ideas about excystment in fossil dinoflagellates, and the dinoflagellate affinity of genera such as Hystrichosphaeridium. Alfred Eisenack did not speak English well, and Bill had only perfunctory German at that time. Despite these communication difficulties, they discussed Bill's emerging hypotheses on fossil dinoflagellates extensively. However Evitt's ideas did not convince Eisenack; moreover, he thought that Bill was entirely wrong. Bill attributed Eisenack's profound unreceptiveness to ‘German stubbornness’, and was frequently significantly frustrated by Eisenack’s stock reply of ‘time will tell’, when Bill explained his new ideas. In particular, Eisenack did not agree with Bill's hypothesis that many Mesozoic and Cenozoic hystrichospheres, such as Hystrichosphaeridium tubiferum, were process-bearing dinoflagellate cysts based on the number and the positions of plate-centred processes (Figure 11; Plate 7, figures 3, 4). This was principally because Eisenack had long been convinced that the hystrichospheres were a coherent group of extinct unicellular algae with a constant basic morphology, and completely unrelated to the dinoflagellates (Eisenack 1954). Despite these professional differences, the two men developed a warm friendship. Perhaps unsurprisingly, they never published together. Although Bill undoubtedly learned much from Eisenack in 1959, and he was impressed at Alfred's very extensive publication record, he clearly felt that some of his scientific contributions were somewhat limited in scope.

Hystrichospheres (literally meaning ‘spiny spheres’) replaced the old term ‘xanthidia’ (Sarjeant 1965; 1967a), and was an informal term used from the description of Hystrichosphaera (now Spiniferites) by Wetzel (1933b) until the 1960s (Sarjeant 1960, 1961). The informal term ‘hystrichospheres’ developed chiefly due to erection of the Family Hystrichosphaeridae and the Order Hystrichosphaeridea by Wetzel (1933b) and Eisenack (1938b), respectively. Alfred Eisenack emphatically did not agree with some of his contemporaries that the hystrichospheres might have dinoflagellate affinity. In one of his early papers, he cited the fact that the reflected fields/plates in hystrichospheres do not break up as in dinoflagellate thecae (Eisenack 1938a). Alfred Eisenack stubbornly clung to the concept of ‘The unity of the hystrichospheres’ (die Einheitlichkeit der Hystrichosphären) for several years after Bill published his then-revolutionary hypotheses regarding fossil dinoflagellates being cysts (Evitt 1961c; Eisenack 1963a, 1963b). In Eisenack (1963a), he strenuously defended his hypothesis that spinose acritarchs and skolochorate dinoflagellate cysts should continue to be termed hystrichospheres. One of his main lines of evidence was the apparent similarities in the walls of acritarchs and hystrichospheres. Eisenack completely rejected the contention that the hystrichospheres were extant (Eisenack 1964), and it was several years later that he (albeit tacitly) accepted the new Evittian paradigm (Eisenack 1969a, 1969b; Eisenack et al. 1973).

Many years later, Bill very much welcomed the description of the Early Cretaceous process-bearing dinoflagellate cyst species Oligosphaeridium abaculum (Plates 9, 10). This magnificent skolochorate species has an unequivocal gonyaulacacean tabulation based on low sutural ridges and plate-centred processes (Davey 1979a). Had Oligosphaeridium abaculum been described in 1959, there would surely have been no dinoflagellate cyst versus hystrichosphere debate. How Bill would have loved to have shown Oligosphaeridium abaculum to Alfred Eisenack in late 1959.

After Bill and Gisela had been in Germany for six weeks, word came in late October 1959 that Elsa Evitt was finding caring for Eric and Steven somewhat difficult, and so Gisela decided to return to the United States immediately. Bill drove her to Bremen to catch a liner to New York. On the way to Bremen they stopped in nearby Barnstorf in Lower Saxony, northwest Germany, to meet Hans Gocht (1930–2014), an extremely promising young palynologist (Figure 15). Hans Gocht originally worked for a German oil company, preparing foraminifera (Riding et al. 2015). Remarkably, he taught himself palynology, and published several papers while working as a technician (e.g. Gocht 1952, 1955, 1957, 1959). Alfred Eisenack quickly recognised Gocht's considerable talents, and encouraged him to return to education to sit his secondary school examinations (Abitur). After doing this, Hans Gocht obtained a PhD and worked under Eisenack at the University of Tübingen. Bill and Hans Gocht were both fascinated by the morphology and fine structure of dinoflagellate cysts, and were extremely analytical and meticulous in their approach. They inevitably became respected colleagues and close friends. In many respects, Hans Gocht was Bill's European contemporary counterpart, and Bill always had the highest respect for Gocht's work. Somewhat surprisingly, they only published together once, in a Festschrift for Alfred Eisenack (Evitt et al. 1985). Bill's final paper is a contribution to Hans Gocht's Festschrift to celebrate the latter's 70^th birthday (Evitt 2001).

Figure 15.

A photograph of the German marine palynologist Hans Gocht (1930–2014) of Tübingen, southwest Germany. The image is taken from Riding et al. (2015), and is used here with the permission of AASP — The Palynological Society.

5.6. A return to the Indian subcontinent

In 1960, Bill was instructed to visit a palaeontological laboratory affiliated with Standard Oil of New Jersey in Calcutta (now Kolkata), India. This was a transglobal trip as he was asked to visit other affiliated laboratories en route. He had some previous experience of Kolkata, having visited twice during his wartime service (subsection 3.3). Two of the local palynologists had studied the sediments of the Ganges Delta in northeastern India. This study was aimed at correlating environments at the surface with their equivalents at depth based on the pollen and spore content of the samples, and Bill's task was to review this work. Bill departed from Tulsa in September 1960; his circumnavigation of the planet included visits to Spain (Barcelona), Libya (Tripoli), Italy (Rome), Greece (Athens), India (Kolkata and New Delhi), Hong Kong and the Philippines (Manila).

The principal task was the visit to the laboratory in Kolkata. After reviewing reports and samples in the office, Bill visited the Ganges Delta itself. The party took a hired boat and sailed south into the more distal areas in the delta right out to the delta front. They returned to the coast and visited Orissa State, southwest of Kolkata, in an area where the meandering distributaries of the Ganges periodically flooded the surrounding land to create an intricate interfingering of dry land, lakes and swamps. The local palynologists had sampled these different modern environments and found distinctive associations of pollen and spores in each. The different depositional settings could then be identified in the subsurface using this ‘palynological fingerprinting’. This work is similar to the study of Muller (1959) in the Orinoco Delta of eastern Venezuela. Bill Evitt was suitably impressed by this work, and reported his findings to Bill Hoffmeister upon his return to Tulsa in November 1960.

5.7. Tulsa turnaround (1960–1962)

Upon Bill Evitt's return to Tulsa from India in late 1960, he turned his attention to a letter received earlier that year from the chairman of the Department of Geology at Stanford University in California. This communication had come completely out of the blue and, in purely professional terms, it was his career watershed moment. The letter was an invitation to work as a visiting professor for six months at Stanford during the academic year 1960–1961. Stanford University is located in Palo Alto, south of San Francisco, California. Specifically, Bill was asked to teach an undergraduate course in palaeontology of his choice and a graduate student seminar during the first half of 1961. Bill had imagined that Jersey Production Research would not allow him to leave for such an extended period, but made enquiries with the company nevertheless. To his considerable surprise (and possibly some mildly hubristic chagrin), he was told that a sixmonth leave of absence could be arranged. Consequently, Bill undertook this temporary teaching position at Stanford University while still permanently employed by Jersey Production Research. So, just before Christmas 1960, the Evitt family drove west to California. A significant domestic change in the Evitt household was that Neisa ten Bruggencate had arrived from Germany to spend a year in the US (subsection 5.5.1). They spent Christmas Day in Gallup, New Mexico, en route before arriving in Palo Alto just before the end of 1960, where they rented a house in Menlo Park.

Bill enjoyed tremendously being back in an academic environment teaching palaeontology and palynology to both undergraduates and graduate students. He also very much liked the Department of Geology at Stanford University, which included good facilities for sample processing. Bill actively explored the geology of the west coast, and undertook several field trips to the Coast Ranges in order to sample the local Mesozoic and Cenozoic strata for palynomorphs. He found several localities which yielded excellent assemblages that were used for PhD studies by his students later in his career. Inevitably, the Evitt family had a wonderful time in California. The spring of 1961 was unusually dry, and they spent virtually every weekend exploring the Bay Area and environs. It was naturally assumed that they would never return to the west coast, and the Evitts were therefore determined to make the most of their six months in San Francisco.

However, on the last day before the long drive back to Oklahoma in June 1961, the department chairman sought out Bill for a chat. He told Bill that they were so impressed with him throughout the visiting professorship that they wanted to offer him a permanent position at Stanford to teach palaeontology, starting in the autumn of 1962. Bill was somewhat taken aback, and did not agree immediately because the family were all happy with life in Tulsa. He requested several weeks in order to seriously consider the offer. Consequently, the Evitt family returned to Tulsa in somewhat thoughtful mood. Neisa helped with settling back into life in Tulsa, before returning to Germany in the autumn of 1961.

The offer from Stanford University in 1961 was truly a bombshell. The initial post in 1960 was strictly for a visiting professor. Furthermore, the Evitts were all contented with life in Tulsa, where professional life for Bill was great and they had all made many good friends. Initially, Bill and Gisela tended to the view that they should stay in Oklahoma. However, on further consideration, they acknowledged that Tulsa had its limitations and their three boys would have better academic, cultural and sporting opportunities in the Bay Area of San Francisco. Moreover, working life at the Jersey Production Research Company was also changing. During Bill's sabbatical in California, Bill Hoffmeister had retired from the Jersey Production Research Company and there were management changes upwards in the heirarchy. These events caused abrupt changes to the atmosphere and focus in the palaeontology group. Without the massively protective and stabilising influence of Bill Hoffmeister, the future of the pure micropalaeontological research programme at Jersey appeared to be under threat. The charismatic Hoffmeister had single-handedly created the unique research-focussed ethos referred to in subsections 5.2 to 5.5. It was inevitable that the Jersey laboratory would henceforth concentrate on routine company projects, and that the highly prized research dimension would be largely lost.

So the lure of the Golden State, together with the changes at Jersey Production Research, led Bill and Gisela to accept the offer from Stanford University subject to the stipulation that he was not to be made departmental chairman. Bill still yearned to teach; he missed the daily interactions with students he had enjoyed so much at Johns Hopkins and Rochester universities. The six years in Tulsa had helped to financially stabilise the Evitt family, and had irrevocably set Bill's career path in palynology. Despite the overwhelmingly positive experience in Oklahoma, Bill was clearly still an academic at heart.

Bill Evitt's final few months at Jersey Production Research were unfortunately somewhat awkward. Although Bill Hoffmeister (who was not present on a daily basis) was supportive, others in the management were not. They made it clear, in these last months, that Bill Evitt was not part of the functioning organisation. It seems likely that, in hindsight, the Jersey management regretted allowing Bill Evitt to have six months’ leave of absence to go to Stanford University in late 1960. It should be stressed here that Bill's scientific and technical colleagues in other parts of the company did not consider him persona non grata. So Bill uncomfortably sat out his notice period and travelled to the Bay Area of San Francisco to house-hunt in the spring of 1962 before the whole family moved to California during the summer of that year.

Lew Stover took over from Bill as senior palynologist at Jersey. Subsequently, the Jersey Production Research Company merged with Humble Oil, and moved from Tulsa to Houston, Texas, to form a new company, Esso (subsequently Exxon and ExxonMobil) Production Research. Lew Stover remained a very good friend of the Evitt family, and he collaborated with Bill on Evitt et al. (1977) and Stover & Evitt (1978). Lew worked at Esso/Exxon in Houston for the remainder of his long and illustrious career (Williams & Partridge 1993).

6.1. Introduction

During Bill's tough final months in Tulsa, there was considerable correspondence with Stanford University regarding his requirements in order to initiate a vibrant research programme in palynology. Bill designed a palynology laboratory based on the one in Tulsa, with preparation facilities at one end and microscopes at the other (Figures 16, 17). This logistical work at Stanford University was financed by a National Science Foundation grant over three years that Bill had successfully applied for to cover fieldwork, a graduate student (John S. Warren), the laboratory and a technician. The latter was Susan E. Davidson (later Thomas), who had taken the palynology course given at Stanford by Bill in 1961. Upon arriving at Stanford in the summer of 1962, Bill oversaw the installation of the palynology laboratory and prepared his undergraduate courses in palynology and invertebrate palaeontology, which were commenced that autumn.

6.2. Family life at Stanford

In 1962, the Evitt family bought a house, 2074 Sandalwood Court, about 5 km from the Stanford University campus. This was close to the boys’ grade school, and also very near to the freeway in eastern Palo Alto. Life in California was good, and provided many unique opportunities. Holidays were spent on excursions to the spectacular Sierra Nevada mountains to the east, including the high country of Yosemite National Park. When the boys were young the family used their camp trailer, and they went backpacking in 1968 and 1969. The latter trip was a six-day hiking trip in the central Sierra, and was their last vacation as a family of five before Eric started college. In the summers of 1964 and 1968, the Evitts took long camping road trips to the east to visit family and friends.

In 1975 the residence rules pertaining to local schools were somewhat relaxed, making it possible for the Evitt family to move from Sandalwood Court, which was rather too close to the freeway, while allowing Glenn Evitt to remain in his high school in Palo Alto. The new home was in the faculty housing area on the Stanford University campus at 882 Cedro Way. This was a much more pleasant environment, and gave Bill a five-minute bicycle ride to his office. The Evitts worked hard on this house; they had it extended to accommodate Gisela's spinning and weaving equipment, fenced off the plot, drained the damp foundations and restocked the garden. This residence served the Evitts well for 29 years, although it was somewhat shaken by the 1989 Loma Prieta earthquake, in which some domestic items were damaged or destroyed (section 13). Bill and Gisela moved to a retirement home at 14500 Fruitvale Avenue in Saratoga, California, in 2004.

Figure 16.

Bill Evitt at his microscope in the palynology laboratory that he established at Stanford University. The image is reproduced with the approval of the Evitt family.

All his life Bill loved using microscopes, and he would often use them informally. One example of this was during his early years at Stanford University. One day while at work, Bill found the vial of iodine crystals he had made as a schoolboy (subsection 2.3) in his office desk. Bill clearly remembered watching the rapidly changing crystals as the iodine melted and recrystallised all those years ago. Intrigued, Bill placed a small amount of iodine from the vial onto a microscope slide, gently placed a coverslip over it, then placed the slide on the hotplate he used for making palynomorph slides. The iodine quickly melted and flowed to the edges of the coverslip, making a superthin layer. The melting point of iodine is 113.7 °C. When the slide was removed from the coverslip, the iodine quickly cooled and recrystallised. Under the microscope, the intensely coloured iodine crystals were spectacular. The playful Bill was now on a roll, and he realised that sulphur has a similar melting point (115.2 °C). Next, he placed small amounts of iodine and sulphur on a slide under a coverslip and heated it as before. The two substances melted and flowed together but, when the slide was allowed to cool, the iodine and sulphur separated and crystals of both elements formed fantastic intergrown shapes. The mixture of crystals was especially aesthetically pleasing due to the light yellow sulphur contrasting sharply with the deep red iodine. Bill reheated the slide several times, and scanned it under the microscope to look for especially photogenic fields of view. He photographed some of these at various magnifications using several levels of cross-polarised light to vary the colour combinations.

Some time later, Gisela audited a course in the Department of Art at Stanford University which was taught by Professor Matt Khan. She thought that Khan and his art class might be interested in Bill's images of the iodine-sulphur slides. The art class was indeed fascinated by the photomicrographs, and Matt Khan asked for copies. He went on to use the images in his art class for the remainder of his career.

6.3. Professional life at Stanford

The Department of Geology at Stanford University (Figure 18) was very strong in several subdisciplines, including palaeontology and stratigraphy, during the early 1960s. Bill obviously was involved in the undergraduate and postgraduate sedimentary geology/soft rock programmes, and was recruited in anticipation of the retirement of some senior faculty members. He taught invertebrate palaeontology, vertebrate palaeontology and palynology. When Bill accepted the position, he insisted that he did not wish to be made chairman of the department (subsection 5.7). In 1962 this duty had an open-ended tenure, but later the chairmanship changed to three-year rotating terms. Bill absolutely preferred research and teaching to administration. The position of departmental chairman for him would have been extremely tedious, verging on anathema. Furthermore, Bill felt that he would not be a good figurehead and that he had little aptitude in fundraising, which was a key role of the chairman. The department willingly accepted this stipulation in 1961, and honoured their commitment thereafter. However, Bill did undertake certain departmental administration duties. For example, he was chairman of the graduate admissions committee for most of his time at Stanford. Bill also served as assistant departmental chair for some of his Stanford tenure and undertook several ad hoc administrative tasks over the years.

Figure 17.

The palynology laboratory at Stanford University. This facility was based on the combined microscope suite and preparation laboratory that Bill Evitt worked in while at Carter/Jersey in Tulsa (section 5). The Stanford University laboratory had chemical preparation facilities to one side and microscopes at the other. These two photographs illustrate Joyce Lucas-Clark working in the laboratory during 1981. The upper photograph (A) shows her at the microscope using several of Bill's dinoflagellate models (section 10). The lower photograph (B) is of Joyce working in the adjacent preparation facility. Note the rubber gloves stored on upright poles to prevent any drops of acid from entering the interior of the gloves, and the centrifuges on both the left and the right. Both photographs are from the personal collection of Joyce Lucas-Clark.

Figure 18.

The Geology Department building at Stanford University, the home of Bill Evitt's palynology laboratory between 1962 and 1988. The specific area illustrated was known as ‘geology corner’. This is part of the overall Stanford University quadrangle, which is a large double quadrangular building with different departments on each of the corners. Photograph by Joyce Lucas-Clark.

At Stanford University, Bill was largely involved in teaching and supervisory duties during term time. He undertook his own research as time permitted, but he found that it was only during the summers that he could really concentrate on this work. His fieldwork, undertaken in the Coast Ranges during his visiting professorship in 1961, provided much valuable sample material and successions for master's and PhD projects, and also for his personal research in palynology. Obtaining good palynomorph assemblages from the western United States is problematical due to the deep weathering profile typical of arid climates. Due to the warm climates during the Cenozoic, most Californian outcrops have been subjected to prolonged and intense weathering, and this has degraded or destroyed much of the palynomorph content by oxidation. This problem can be overcome by carefully selecting fresh material, sampling very hard lithotypes such as early diagenetic limestones and nodules, or exclusively using borehole material. If lithification is intense as in some nodules, and this occurs early in diagenesis, the fossils will have been protected from post-depositional compaction and weathering. Bill found that the Lower Cretaceous limestones and calcareous concretions of northern California, and the phosphatic concretions from the Upper Cretaceous of central California produced especially abundant and well-preserved dinoflagellate cysts. These distinctive lithotypes were therefore targeted in sampling campaigns. John S. Warren based his PhD on Jurassic and Lower Cretaceous limestones and calcareous concretions from the west side of the Sacramento Valley (Warren 1967, 1973; Warren & Habib 1971; Habib & Warren 1973). The Upper Cretaceous phosphatic nodules provided material for the PhDs of Carol A. Chmura and Jeffery A. Stein (Appendix 2; Chmura 1973).

Communication between all the geologists working in the Palo Alto area was good. Bill asked Bob McLaughlin and his colleagues at the United States Geological Survey (USGS) office at Menlo Park, close to the Stanford University campus, to send for processing any material for which they needed biostratigraphical analyses. This led to a steady flow of samples submitted to Stanford by USGS geologists working in the Californian coastal ranges and northwards into Oregon. The biostratigraphical conclusions provided by Bill were included in publications such as Berkland (1973), Blake & Jones (1974, table 1), Maxwell (1974), Gucwa (1975, table 2) and McLaughlin et al. (1984). Bill used the scanning electron microscope (SEM) at the USGS Menlo Park office, operated by Bob Oscarson. As such, he was one of the first palynologists to use this instrument.

The most important of the USGS material were limestone samples from Mendocino County in the Coastal Belt of the Franciscan Complex, west of the Sacramento Valley in northern California. This terrane, which comprises many accreted blocks of disparate provenance (Wakabayashi 1992), was originally thought to be extremely sparsely fossiliferous. The Coastal Belt had yielded some tentative indications of Late Cretaceous ages (Bailey et al. 1964). However, Bill and his master's student Sarah Pierce (later Damassa) recovered abundant assemblages of Cretaceous and Eocene dinoflagellate cysts (Evitt & Pierce 1975; Damassa 1979a, 1979b). By contrast, the Franciscan rocks to the east yielded Cretaceous palynomorphs (Evitt & Pierce 1975). The discovery of Eocene rocks in the Franciscan Complex was very surprising at the time, and caused a revision of the standard interpretation of the Northern Coast Ranges of California (Berkland et al. 1972; Blake & Jones 1974). Bill also processed several samples of the Monterey Formation, of Miocene age, from California. This organic-rich unit is rich in calcareous nannofossils, diatoms and foraminifera, but yielded sparse, poorly preserved marine palynomorphs.

Plate 8.

Four of the 35-mm transparency slides included in the ringbound file of course materials that Bill Evitt provided to participants of the two-week Teaching Conferences on Fossil Dinoflagellates (section 10). These slides accompanied the practical exercises and the specimens for study. These three specimens are all skolochorate forms. All the images are reproduced with the approval of the Evitt family.

Figures 1, 2. Spiniferites pseudofurcatus; two specimens in ventral and antapical view, respectively, both at high focus; Calvert Formation, Miocene, Maryland. These were slides 8 and 9. This is a relatively long-ranging species; it has been recorded from the Late Cretaceous (Late Turonian) to the Late Miocene (Tortonian) (Foucher 1976; 1979; Powell 1992). It is most prominent in the Palaeocene to Miocene interval, and the type is from the Late Eocene of Germany (Klumpp 1953). Spiniferites pseudofurcatus was emended by Sarjeant (1981, p. 108–109). It has a characteristically ovoidal/subpentagonal cyst body, typically smooth autophragm and low, distally smooth sutural crests which are markedly suppressed in the midventral area. Note the prominent gonal processes which are distally open, hollow, trifurcate and triangular in cross section. The hollow and distally open nature of the processes is unusual for this genus. Some of the processes merge proximally. The first-order distal branches of the processes are variable in morphology; they may be distally blunt, concave, pointed or furcate. In Figure 1, note the wide, sulcal region and the prominent 6” plate. Figure 2 illustrates the 1”” plate which is surrounded by the ps, 1p, 3’”, 4’”, 5’”and 6’” plates (from the top, clockwise). The 1”” plate exhibits a suturocavate organisation (Riding 1983; Evitt 1985, figs 4.1P—R). In Figure 1 the cyst body is 90 µm in diameter, and the overall dimensions including the processes are 150 µm long by 140 µm wide. The cyst body and the overall specimen (including processes) of Figure 2 are 90 µm and 130 µm in diameter, respectively.

Figure 3. Homotryblium tenuispinosum, ventral view, high focus; London Clay Formation, Lower Eocene (Ypresian), southern England. This was slide 12 and Bill termed it Homotryblium sp. The specimen was first published in Evitt (1967c, pl. 9, fig. 7) as Forma AC. Homotryblium is a skolochorate gonyaulacacean genus with distally expanded and open, hollow, plate-centred processes. The archaeopyle is of combination type [A(3A)6P]. This excystment aperture is unique amongst sexiform gonyaulacaceans in that all the apical and precingular plates are involved in a compound archaeopyle. Moreover, plates 2’. 3’ and 4’ are lost as a single piece, and all seven others are dehisced individually (Evitt 1985, figs 6.4L, 6.10R; Fensome et al. 1993, fig. 113D). The most similar archaeopyle type is in Mancodinium, but this genus has a significantly different epicystal tabulation (Morgenroth 1979; Fensome et al. 1993, fig. 70C). This means that, when the archaeopyle is fully operated, there are eight separate opercular pieces. Homotryblium tenuispinosum is characterised by its ovoidal cyst body, granulate autophragm and relatively slender, tubiform, distally open plate-centred processes with aculeate to serrate terminations (Davey & Williams 1966, p. 101 – 102). The combination archaeopyle is forming in this very well-preserved specimen; note the major dehiscence immediately anterior of the cingulum. The ventral tabulation is clearly discernible. The most obvious plates are 1’, 4’, 1”, 6”, 1c, 6c, 2’”, 6’”, 1p, 1”” and as. The latter plate forms the prominent sulcal tab. The cyst body is 63 µm long, and 65 µm wide; the overall diameter, i.e. including the processes, is 105 µm.

Figure 4. Homotryblium sp. cf. H. tenuispinosum, antapical view, high focus; London Clay Formation, Lower Eocene (Ypresian), southern England. This was slide 13 and Bill termed it Homotryblium sp. It is attributed here to Homotryblium sp. cf. H. tenuispinosum because it has a smooth, and not granulate, autophragm. The 1”” process is in the centre and is not in sharp focus, the slender sulcal processes are visible at the top of the specimen, and the large equatorial processes are largely from the postcingular series. The diameters of the cyst body and the entire cyst including processes are 50 µm and 90 µm, respectively.

The departmental collections at Stanford University, in particular samples collected for foraminifera by Hubert G. Schenck from Europe and the United States, also produced good samples for Bill's research. Schenck was an eminent micropalaeontologist and stratigrapher (Schenck & Muller 1941), who died shortly after World War II. This collection was curated in shoe boxes, and stored in the attic of the geology building at Stanford. Bill found much excellent material from this collection, including samples from the Lower Eocene London Clay Formation of southern England and material from some early Californian oil wells.

Bill ordered a small plankton net for use in local lakes and ponds, and the nearby coastline. It arrived while he was away from the department, and Susan Davidson took the net to rockpools on the Pacific shore in nearby San Mateo County where she found a very rich assemblage of living marine dinoflagellates. The net was attached to a long pole, and a fishing weight was used to submerge the net. The net was towed through the surface water, and the catch was occasionally washed into a collecting bottle. Most of the catch remained alive for up to a few days, and was eventually preserved by adding a small amount of ethanol. Susan Davidson made microscope slides of the Pacific dinoflagellate material, both raw and some processed using hydrofluoric acid. These were the first living marine dinoflagellate cysts that Bill had ever seen. The material largely included empty cysts with open archaeopyles and isolated cysts with granular protoplasm. Other plankton net material from Drøbak Sound, Oslo Fjord, Norway, provided by Trygve Braarud, yielded an extremely important specimen. This was an organic-walled cyst referred to Hystrichosphaera (now Spiniferites) inside a partly broken theca of Gonyaulax digitale (Plate 11). Of course this specimen unequivocally proved Bill's earlier contention that organic dinoflagellates represent the cyst stage. It exhibited exactly the relationship of cyst and theca hypothesised in Evitt (1961c). This specimen was published in Evitt & Davidson (1964, pl. 1, figs 10, 11). Unfortunately, Bill never found another specimen of a cyst within a theca in this material. However, he later observed cyst-theca relationships in Protoperidinium from other Pacific coastal samples, but these were never published. This means, therefore, that Evitt & Davidson (1964) was among the first convincing indications of the true nature of fossil dinoflagellates in terms of the life cycle, i.e. that they represent benthic resting cysts.

Plate 9.

Topotype material of the distinctive Early Cretaceous skolochorate dinoflagellate cyst species Oligosphaeridium abaculum. The photomicrographs were all taken using differential interference contrast (DIC). All the specimens are from British Geological Survey (BGS) offshore United Kingdom borehole 77/80B at 78.95 m. Borehole 77/80B was drilled during June 1977, 30 km northeast of Unst, Shetland Isands in the East Shetland Basin, northern North Sea (Davey 1979a). The sample is at the terminal depth in this well and is of a Lower Barremian mudstone within the Cromer Knoll Group (undivided). The palynomorph preparation is BGS registration number CSC 1824. Note the subcircular dorsoventral outline of the cyst body, the prominent hollow, distally open, expanded and furcate plate-centred processes, and the apical archaeopyle. This species is unique in that it exhibits low sutural ridges which define a standard gonyaulacacean tabulation pattern. The formula is 1pr, 4', 6'', 6c, 6''', 1p, 1'''', 5s. Oligosphaeridium abaculum is a reliable marker for the Late Hauterivian to the earliest Barremian interval (Costa & Davey 1992). In the North Sea, it is common throughout its relatively short range, which spans the latest Hauterivian to earliest Barremian (Simbirskites marginatus ammonite biozone to within the Simbirskites variabilis ammonite biozone) in the central North Sea according to Duxbury (2001, fig 17). Its biogeographical distribution in the North Sea indicates that Oligosphaeridium abaculum was a high-latitude, Boreal species.

Figures 1, 2. British Geological Survey (BGS) specimen number MPK 14563, slide CSC 1824/6, England Finder coordinate J62/4. A loisthocyst in ventral view, high and low focus, respectively. Note the prominent sulcal notch, and the faintly indicated cingulum and sulcus in 1. The cyst body is 49 µm long and 60 µm wide, the overall length and width are both 95 µm, and a typical processes is 27 µm in length. The scale bar in 2 represents 50 µm.

Figures 3, 4. BGS specimen number MPK 14564, slide CSC 1824/3, England Finder coordinate H67. A loisthocyst in antapical view, low and high focus, respectively. The sulcus is uppermost in both photomicrographs. Note the principal archaeopyle suture in figure 3, and the antapical (1'''') and surrounding postcingular plates in figure 4. The diameter of the cyst body is 53 µm, the overall diameter is 102 µm and a typical processes is 31 µm long. The scale bar in figure 4 represents 50 µm.

Figures 5, 6. BGS specimen number MPK 14565, slide CSC 1824/6, England Finder coordinate F57/4. A loisthocyst in oblique dorsal view, low and high focus, respectively. Note the prominent sulcal notch in figure 5; the as and 6'' plates are especially prominent. The central plate in figure 6 is the middorsal postcingular (4'''); note also the narrow cingulum. The cyst body is 60 µm long and 56 µm wide, the overall length and width are 129 µm and 111 µm, respectively, and a typical processes is 40 µm in length. The scale bar in 6 represents 50 µm.

David Wall and Barrie Dale were also working on modern dinoflagellate cysts on the east coast of the United States at Woods Hole Oceanographic Institution in Massachusetts at that time. Wall (1965, figs 24–29) illustrated the excystment of a cyst of Spiniferites bentorii that had been incubated. The relevance of Evitt & Davidson (1964) was only discussed by David Wall in an addendum (Wall 1965, p. 312–313). It is now clear that David Wall and Barrie Dale made the discovery regarding the cyst-theca relationship at virtually the same time as Bill and Susan Davidson did. The Wall and Dale team established the detailed life cycle of cyst-producing dinoflagellates experimentally by observing the production of cysts inside dinoflagellate thecae, and the incubation and excystment of modern dinoflagellate cysts. David Wall, Barrie Dale and their colleagues continued to extensively research dinoflagellate encystment and excystment using incubation experiments (e.g. Wall & Dale 1966, 1968a, 1969, 1970; Wall et al. 1967; Wall 1971; Dale 1977, 1983; Anderson & Wall 1978). The work of Wall and Dale was briefly reviewed by Head & Harland (2004a, 2004b).

Bill worked with modern plankton in a collaboration with David Wall (Evitt & Wall 1968). This study was chiefly on the thecate species Peridinium limbatum from Round Pond, Falmouth, Massachusetts. The locality is close to Woods Hole Oceanographic Institution, where David Wall worked. This contribution was a detailed study of cyst development in Peridinium limbatum, and includes the first ever SEM images of dinoflagellates (Plate 12; Evitt & Wall 1968, pl. 1, figs 1–4). Bill also used the plankton net in the freshwater ponds and lakes around Stanford University, including Felt Lake, and discovered several species of Ceratium in assemblages containing abundant active thecate individuals and fewer numbers of cysts. The cysts were both isolated and inside the motile stage. He found that the thecae in some of these samples would largely encyst if left unattended for several days. These associations of Ceratium were the basis for another major collaboration with David Wall on modern and fossil ceratioid forms (Wall & Evitt 1975).

At the same time as he was making great break-throughs in dinoflagellate research, Bill also added to his teaching repertoire. He developed a survey (i.e. textbook-based) course on vertebrate palaeontology. This was instigated due to the high-profile discovery of a specimen of the large aquatic herbiferous mammal Palaeoparadoxia in a trench in Miocene strata which was being dug for the Stanford Linear Accelerator Center (SLAC) about 1.5 km from the main university campus during 1964 (Inuzuka 2005; Domning & Barnes 2007; Barnes 2013). This virtually complete skeleton was excavated and reassembled by Adele I. Panofsky. She assembled the Palaeoparadoxia bones, and constructed displays for the University of California Berkeley Museum of Paleontology and SLAC. Adele Panofsky taught herself by consulting with experienced vertebrate palaeontologists, having no previous experience in this subject (Panofsky 1998). Bill's graduate seminar classes visited Adele Panofsky and the Palaeoparadoxia bones until they were complete and on display at SLAC. The course on vertebrate palaeontology was planned as a one-off delivery by Bill, but it proved so popular that the module was presented another 15 times during the next 20 years. One of us (JL-C) remembers the exquisite chalk drawings Bill spontaneously produced while teaching the class. Incidentally, Bill was asked by the then chair of the department, Ben Page, to investigate the palynology of some samples from this trench. This material produced some poorly preserved Palaeogene dinoflagellate cysts.

Plate 10.

A direct comparison of the tabulate chorate dinoflagellate cysts Oligosphaeridium abaculum and Oligosphaeridinum complex; the latter lacks sutural ornamentation. All specimens were photographed using DIC, except figure 5 which was taken using plain transmitted light. Oligosphaeridium abaculum was fully described in the caption to Plate 9 (above). Oligosphaeridinum complex has a subcircular cyst body in outline, and a smooth to occasionally microgranulate cyst wall, and bears cylindrical, distally expanded, branched and open plate-centred processes in all plate series except the cingulars. The processes typically bear four to six simple or occasionally bifurcate branches at the distal end, which is normally aculeate or secate. This distinctive species is most common in the Early Cretaceous; its total range is Early Cretaceous (early Valanginian) to Eocene (early Lutetian) (Costa & Davey 1992; Stover et al. 1996, figs 24A, 32).

Figures 1, 3, 5. Oligosphaeridinum complex. All of the specimens are from drill cuttings between 4047.74 m and 4044.70 m in central North Sea well 22/1-2A; this interval is within the Lower Cretaceous Cromer Knoll Group.

Figure 1. BGS specimen number MPK 14586, slide MPZ 7780/1, England Finder coordinate 036/4. An isolated operculum; note the 1’ plate in the top right. At the base of the four processes, a distinct ring indicates where the periphragm (which forms the processes) has separated from the endophragm. The length (the dorsoventral dimension, excluding the processes) is 38 µm, and the width (the lateral dimension, excluding the processes) is 31 µm. The length of the 1' process at the top right is 31 µm. The scale bar represents 20 µm.

Figure 3. BGS specimen number MPK 14587, slide MPZ 7780/1, England Finder coordinate L33/3. A loisthocyst in dorsal view, high focus. Note the apical archaeopyle, the clear lack of cingular (equatorial) processes and the prominent, straight plate-centred processes. The cyst body is 49 µm long and is 51 µm wide, the overall length and width are 91 µm and 100 µm, respectively, and a typical process is c. 29 µm in length. The scale bar represents 25 µm.

Figure 5. BGS specimen number MPK 14588, slide MPZ 7780/1, England Finder coordinate T46/3. A loisthocyst with (its presumed) operculum, ?oblique right lateral view, high-median focus. Note the similar height of the processes; it is easy to visualise the distal ends of them adjacent to the inner thecal wall of the parent cell. The cyst body is 62 µm in both length and width, and the overall length and width are both 118 µm; a typical processes is c. 38 µm in length. The scale bar represents 20 µm.

Figures 2, 4, 6. Oligosphaeridium abaculum. All specimens are topotypes from the East Shetland Basin (see the caption to Plate 9). Figure 2. BGS specimen number MPK 14589, slide CSC 1824/5, England Finder coordinate P54/4. An isolated operculum; note the clear sutural ridges, the single preapical plate and the relatively small 1' plate in the top right. The four circular features at the base of the processes clearly indicate the separation of periphragm and endophragm. The length (the dorsoventral dimension, excluding the processes) is 42 µm, and the width (the lateral dimension, excluding the processes) is 36 µm. The length of the 3’ process at the bottom left is 31 µm. The scale bar represents 20 µm.

Figures 4, 6. BGS specimen number MPK 14590, slide CSC 1824/5, England Finder coordinate R65/2. Specimen in ventral view, high and low focus, respectively; note the apical archaeopyle. This superbly preserved specimen clearly demonstrates the gonyaulacacean tabulation and the plate-centred processes. The sulcus is visible in figure 4, as is the middorsal postcingular plate (4''') immediately below the cingulum in 6. The cyst body is 56 µm long and 53 µm wide, the overall length and width are 98 µm and 109 µm, respectively, and a typical processes is 31 µm in length. The scale bar represents 25 µm.

Bill, his graduate students and some paid assistants including Susan Davidson and Martha Helenes at Stanford University continued with the fossil dinoflagellate genus and species card index file he had begun while at the Jersey Production Research Company in Tulsa during the 1950s (Figure 19; subsection 5.4). When Bill ceased active research in 1989, it had around 10,000 entries. Publishing this index, much in the style of Georges Deflandre, had been considered but advances in electronic copying information, especially using CDs, rendered this superfluous. When Bill retired, the dinoflagellate cyst card index and his entire reprint collection were donated to the Center for Excellence in Palynology (CENEX) at Louisiana State University in Baton Rouge, Louisiana. His microscope slide collection was transferred to the University of California Berkeley Museum of Paleontology under the curatorship of Ken Finger, while the rock samples are now housed at Clark Geological Services, under the care of Joyce Lucas-Clark.

Bill's career at Stanford saw many breakthroughs in the earth sciences, including plate tectonics and sequence stratigraphy. Furthermore, Bill witnessed many changes locally and further afield. Federal funding for faculty and student research, largely via grants from the National Science Foundation, diminished significantly during Bill's tenure. His graduate students were funded from diverse sources, such as their home governments for the non-United States citizens, the GSA, oil companies, the USGS or directly from Stanford University. In the department, mineralogy/petrology and structural geology increased in strength, and basin analysis and environmental geology were instigated and thrived. The corollary of these trends was a decline in palaeontology and stratigraphy. The Stanford University department remains very strong today, especially in modern technologically driven disciplines. It is larger and significantly more diverse than in Bill's time there. Palaeontology is still taught, but it is not as prominent today as it was in the early 1960s.

Plate 11.

A dinoflagellate cyst produced by a theca of Gonyaulax digitale; this cyst is clearly referable to the genus Spiniferites. The specimen is from a plankton net sample taken from Drøbak Sound, Oslo Fjord, Norway on 9 September 1950 (Evitt & Davidson 1964, p. 5). Both images are from Evitt & Davidson (1964, pl. 1, figs 10, 11 respectively) and are reproduced with the approval of the Evitt family. These images, originally published by Evitt & Davidson (1964), are among the first illustrations of the relationship of a cyst-producing dinoflagellate theca and its cyst. They confirmed that dinoflagellate cysts are benthic resting bodies, and this is entirely consistent with the cyst-theca relationship first hypothesised by Evitt (1964, pl. 1, figs 15–17).

Figure 1. The spinose cyst of Gonyaulax digitale is filled by dark cytoplasm, and some of the disaggregated thecal plates are adherent; note those in the apical region and on the bottom right. The scale bar represents 25 µm.

Figure 2. The same specimen following treatment with sodium hypochlorite solution. This reagent has destroyed the thecal plates and bleached out the protoplasm, making the specimen of Spiniferites much easier to study. The scale bar represents 25 µm.

Bill was not replaced by a palynologist when he retired in 1988, and his dynasty was, unfortunately, not continued. The principal connection with dinoflagellates at Stanford University in the post-Evitt era was the appointment of J. Michael Moldowan who worked on the chemical fossil record, specifically molecular fossils (biomarkers). Moldowan’s work has helped to elucidate the early history of the dinoflagellates (e.g. Moldowan et al. 1996, 2001; Moldowan and Talyzina 1998; Talyzina et al. 2000; Zhang et al. 2000). Significantly, this biogeochemical research has supported Bill's long-held hypothesis that dinoflagellates can switch on and off the ability to produce preservable fossil remains (subsection 9.4).

Because Bill worked at Stanford University during most of the 1960s, he witnessed many socio-political changes. He commented that the profound student unrest of the late 1960s came to rather conservative Stanford relatively late. However, the tensions that had gripped most campuses in the United States arrived in Palo Alto at the turn of that febrile and precipitous decade. There were building closures, fires, protests and strikes on the campus which undoubtedly affected both research and teaching. Bill recalled that the university authorities had the ornamental cobbles which surrounded the campus gardens replaced with far less dangerous pea gravel.

6.4. Graduate students at Stanford University

Bill supervised 11 PhD students and five master's students at Stanford University (Appendix 2). The PhDs graduated in two principal phases. The first cohort comprised John S. Warren, who graduated in 1967, followed by Neely H. Bostick in 1967, Carol A. Chmura McLeroy in 1970 and Dewey M. McLean in 1971. There then followed a 12-year hiatus until both David K. Goodman and Jeffrey A. Stein graduated in 1983. The other PhD graduates in this second wave were Anthony N. Bint in 1984, Javier Helenes-Escamilla in 1984, Joyce E. Lucas-Clark in 1986, Nairn R. Albert in 1988 and David I. Wharton in 1988. Several of the dissertations produced by these students are in the public domain (e.g. Albert 1988; Wharton 1988a). Fred E. May was not a graduate student of Bill. Although he frequently communicated with Bill about his research, Fred May was never a student at Stanford University. He was a student of Dewey M. McLean at Virginia Polytechnic Institute and State University, Blacksburg, Virginia, and hence was a ‘graduate student once removed’ of Bill's.

Plate 12.

A scanning electron microscope (SEM) image of an entire theca of the modern freshwater dinoflagellate Peridinium limbatum in oblique ventral view. Note the sub triangular dorsoventral outline, the three polar horns, the prominent, highly indented cingulum and sulcus, the regularly reticulate thecal wall, and the striate growth bands which separate the original plate areas. The theca is 94 µm long, and has an equatorial width of 68 µm. This specimen of Peridinium limbatum from Round Pond, Falmouth, Massachusetts, together with others in Evitt & Wall (1968) are believed to be the first ever SEM images of dinoflagellates to be published. They were taken at the Cambridge Instrument Company, Chicago, at a promotional demonstration of the Stereoscan SEM shortly after this model became available. This image was originally published in Evitt & Wall (1968, pl. 1, figs 2, 3), and by Evitt et al. (1998, pl. 1, fig. 5). It is reproduced with the permission of AASP — The Palynological Society.

Only two of these PhD projects, those of Neely H. Bostick and Carol A. Chmura McLeroy, were not on dinoflagellate cysts. The former was on the thermal alteration of phytoclasts as a proxy for metamorphism (Bostick 1971, 1974), and the latter concerned Late Cretaceous angiosperm pollen from the western San Joaquin Valley of California (Chmura 1973). The nine other Stanford PhD dissertations were all on dinoflagellate cysts. They comprise three on the Late Jurassic and Cretaceous of California, two on the Middle Jurassic to Early Cretaceous of Alaska, one on the Mesozoic and Cenozoic of Mexico, one on the Cretaceous of the Western Interior of the United States and two on the Late Cretaceous to Eocene of Maryland and Virginia (Appendix 2). Most of these studies have had at least some of their findings published (McLean 1971, 1972, 1973a, 1973b, 1974, 1976; Warren & Habib 1971; Habib & Warren 1973; Warren 1973; Goodman 1979, 1984; Bint 1983, 1986; Goodman & Ford 1983; Helenes 1983, 1984, 1986, 2000; Lucas-Clark 1984, 1986, 1987, 2007; Goodman & Witmer 1985; Albert et al. 1986; Jan du Chêne et al. 1986a; Ford & Goodman 1987; Wharton 1988b; Albert 1990; Helenes & Lucas-Clark 1997; Lucas-Clark & Helenes 2000). Even a casual glance at the previous list of publications will make clear that Bill allowed his graduate students sole authorship of their work, despite having himself made an enormous material contribution to these. If Bill was a co-author, he had assuredly made a major contribution to both the research and the writing effort.

Master's students at Stanford included Sarah T. Pierce and John P. Kokinos. Both of them clearly enjoyed the research environment, because they went on to undertake PhDs at the University of California, Los Angeles, and Woods Hole Oceanographic Institution, Massachusetts, respectively (Damassa 1979c; Kokinos 1994). In addition to these graduate students, the South Korean palynologist Hyesu Yun visited Stanford University to undertake a postdoctoral research project during the summer of 1980.

Bill took his supervisory duties very seriously and gave each graduate student an individual two-week induction course during which they learned his methods of processing, individual dinoflagellate picking and manipulation, and microscopy (Appendix 5). In particular, he really enjoyed supervising his relatively large and diverse cohort of research students during the 1980s. This was when he supervised Nairn Albert, Tony Bint, Javier Helenes, John Kokinos, Joyce Lucas-Clark and David Wharton. This large number of Stanford palynologists formed a very congenial and sociable group. They all shared a single large, open-plan office, and got along famously. All of them enjoyed the regular weekly afternoon seminar at Bill and Gisela's house on the campus, where dissertation progress was reviewed and wider palynological topics were discussed.

Figure 19.

Martha Helenes working on updates to the alphabetical card index of dinoflagellate cyst genera and species in the palynology laboratory at Stanford University in 1981. The index was begun in the 1950s, while Bill Evitt was at Carter/Jersey in Tulsa, and continued at Stanford. Photograph by Joyce Lucas-Clark.

9.1. Introduction

Of all his many and varied scientific endeavours, it is for his groundbreaking and unique research into Mesozoic and Cenozoic marine palynomorphs that Bill Evitt will always be remembered. He published 48 papers on aquatic palynomorphs, dominantly dinoflagellate cysts (Table 4). Bill described, or jointly described, 23 new genera and 10 new species of acritarchs and dinoflagellate cysts (Table 4). In this section, Bill's work on acritarchs and dinoflagellate cysts is reviewed. There are also subsections on the selectivity of the fossil dinoflagellate cyst record, and on his two major textbooks, Stover & Evitt (1978) and Evitt (1985).

9.2. Acritarchs

One of Bill Evitt's finest achievements was the resolution of the question of the hystrichospheres (Evitt 1961c, 1963a, p. 159–160). As explained in subsection 5.5.2, prior to the early 1960s, all spinose marine palynomorphs were assigned to this informal group, which was championed by Eisenack (1938b, 1963a, 1963b, 1964). Bill elegantly demonstrated that the Mesozoic to Cenozoic hystrichospheres with a distinct archaeopyle and plate-centred processes were of dinoflagellate affinity (e.g. Evitt 1961c). Hystrichospheres that could not be confidently assigned to the dinoflagellates, and are hence of unknown affinity, were termed acritarchs. The classification of these palynomorphs as hystrichospheres could not be maintained because genera such as Hystrichosphaera (now Spiniferites) and Hystrichosphaeridium clearly are dinoflagellate cysts (Plates 7, 8). Consequently, if the status quo had prevailed, there would inevitably have been endless confusion over the affinity of the pre-Mesozoic hystrichospheres. Hence, a new name was urgently needed. Despite this, at the outset, the introduction of the acritarchs as a concept was somewhat controversial, largely due to strenuous opposition by Alfred Eisenack (subsection 5.5.2; Sarjeant 1998, p. 4).

Acritarchs were defined thus: ‘Small microfossils of unknown and probably varied biological affinities consisting of a central cavity enclosed by a wall of single or multiple layers and of chiefly organic composition; symmetry, shape, structure and ornamentation varied; central cavity closed or communicating with the exterior by varied means, for example: pores, a slit-like or irregular rupture, a circular opening (the pylome)’ (Evitt 1963b, p. 300). A more succinct definition would be ‘A single-celled, organic-walled microfossil of unknown affinity’ (Fensome et al. 1993, p. 249). All 10 published definitions of the acritarchs were compiled by Williams et al. (2000, p. 3–4).

The acritarchs were therefore formally established in Evitt (1963b, p. 300–302; see Appendix 3). As outlined above they represent a highly variable group of dominantly marine forms of unknown affinities, and are probably polyphyletic. They originated during the late Precambrian, but are largely Palaeozoic. During the Early and Middle Palaeozoic, marine phytoplankton largely comprised acritarchs (Fensome et al. 1990; Falkowski et al. 2004). There is now a significant literature on the acritarchs, which are important stratigraphical markers in the Early Palaeozoic (e.g. Downie 1984; Martin 1993; Colbath & Grenfell 1995; Strother 1996). The majority of Late Precambrian and Palaeozoic acritarchs are considered to represent the cysts of unicellular planktonic organisms, analogous to the cysts of modern dinoflagellates, but probably having affinities with the green algae (Tappan 1980; Servais et al. 1997; Martin et al. 2008; Traverse 2008; Moczydłowska et al. 2011). It is also possible that some Early Palaeozoic acritarchs represent microalgal motile stages (Moczydłowska 2010). The group is still widely acknowledged to be polyphyletic (e.g. Fensome et al. 1990, p. 3).

The account of the acritarchs in Evitt (1963b, p. 300–302) was rather brief. Downie et al. (1963, p. 7) expanded the definition to specify that acritarchs were ‘unicellular or apparently unicellular’, and added several descriptors of the shapes and ornamentation of typical acritarchs. These authors also presented a formal taxonomy, defined 13 subgroups and stated which existing genera should be attributed to the Acritarcha (Appendix 3). Following Downie et al. (1963), Bill did not work extensively on the acritarchs; his palynological interests were always firmly rooted in the Mesozoic and Cenozoic. One of Bill’s few forays into pre-Mesozoic palynology was his work on the Early Silurian Maplewood Shale Formation of western New York State, which he began while working at the Carter Oil Company (subsection 5.4). Much later, this led to his only paper solely on acritarchs. This was Deunff & Evitt (1968), in which three species of the acritarch genus Tunisphaeridium were erected (Appendix 3; Table 4). The only other contribution Bill made on acritarchs was an extensive synthesis of the group in a review paper which was largely on dinoflagellate cysts (Evitt 1969, p. 463–468; see Appendix 3).

Table 4.

A tabulated synopsis of the 48 research papers and books on aquatic palynomorphs authored by Bill Evitt and his co-workers. The numbers of the publications are the ones used in Appendix 3. The 16 most important contributions are indicated with an asterisk. An ellipsis (…) in the three columns indicating new taxa means that none of that respective rank were erected. Note that Evitt (1984) is also listed in Table 3.

Plate 13.

Four scanning electron microscope (SEM) images of Nannoceratopsis deflandrei subsp. senex from the early Aalenian Tmetoceras scissum ammonite biozone (Middle Jurassic) of southern England. The photomicrographs are all taken from Piel & Evitt (1980a), and clearly demonstrate the overall cyst organisation and the unique cingular (type C) archaeopyle. The images are reproduced with the permission of AASP — The Palynological Society.

Figure 1. Slightly oblique apical view. Note the small epicyst with clearly subdivided plates, above the markedly concave cingulum and the strongly perforate autophragm; the middorsal plate 3c forms the archaeopyle. The highly indented sulcus is on the ventral side (facing downwards here), directly opposite the archaeopyle. This image was pl. 1, fig. 7 of Piel & Evitt (1980a).

Figure 2. A specimen in slightly oblique dorsal view. The image demonstrates the profound disparity in the size of the epicyst and hypocyst. Note the clear sagittal suture between the two large hypocystal plates H₂ and H₃ within the prominent sagittal band (median groove), which is somewhat striated. These transverse lineations are interpreted as reflected growth features (megacytic zones) from the parent theca. This image was pl. 2, fig. 4 of Piel & Evitt (1980a).

Figure 3. A well-preserved specimen in dorsal view. The cingular archaeopyle and the sagittal suture are especially prominent. This image was pl. 2, fig. 3 of Piel & Evitt (1980a).

Figure 4. A specimen in dorsal view; note that the operculum (plate 3c) is in place. This image was pl. 2, fig. 5 of Piel & Evitt (1980a).

9.3. Dinoflagellate cysts

The majority of Bill Evitt's scientific efforts during his long and distinguished career were spent undertaking research on the dinoflagellates, and especially their cysts. This and the following three subsections seek to document the massive impact Bill had (and continues to have) on the world of dinoflagellate research.

Bill Evitt made his biggest career move in the late summer of 1956 when he moved from the University of Rochester, where he researched trilobites, to the Carter Oil Company in Tulsa where he was to study marine palynomorphs (sections 4, 5). His line manager at Carter Oil, Bill Hoffmeister, presented Bill Evitt with a magnificent collection of prepared material from throughout the Phanerozoic which was rich in fossil dinoflagellates and hystrichospheres. At this time, there were very few publications on these palynomorph groups, so Bill Evitt had virtually a blank canvas to work on (section 5). He took full advantage of this excellent position to use his acute observational skills on a wide variety of fossil dinoflagellates and hystrichospheres. The first breakthrough by Bill Evitt at Tulsa was in the late 1950s with the realisation that certain well-preserved hystrichospheres have definite dinoflagellate affinity, based on an archaeopyle which corresponds to one or more plates and plate-centred processes (Figure 11; Plates 7–11; Evitt 1963a, fig. 3). Bill Evitt's research on dinoflagellate cysts is well documented elsewhere (sections 5, 6, 10, 11; Appendix 3; Table 4), so a detailed analysis of this is not repeated here. This short section, by contrast, aims to summarise Bill Evitt's massive contribution to our knowledge of Mesozoic—Cenozoic sporopollenin dinoflagellate cysts. Bill Evitt himself felt that his four most impactful publications were (Evitt 1961c), Evitt & Davidson (1964), Evitt (1967c) and Evitt et al. (1998) (see Leffingwell & Damassa 2004).

Bill Hoffmeister encouraged his staff to publish, and Bill Evitt issued three publications on dinoflagellate cysts during his six-year industrial sojourn in Tulsa (Evitt 1961b, 1961c, 1961d). By far the most significant of these was Evitt (1961c), entitled Observations on the morphology of fossil dinoflagellates. This paper was the first indication that the dinoflagellate fossil record is mostly represented by the resting cyst stage, and that dinoflagellate cysts reflect the tabulation of the parent theca. However, Evitt (1961c) stated that some (largely proximate) fossil dinoflagellates were thecae due to their strong resemblance to the motile stages of certain modern forms. These are now known to be dinoflagellate cysts. The other key elements of this work were (i) many hystrichospheres were recognised as being dinoflagellates, based largely on analysis of Hystrichosphaeridium and Spiniferites (as Hystrichosphaera), and (ii) the archaeopyle was first defined. Evitt (1961c) recognised that the excystment aperture of dinoflagellate cysts is widespread, and that the operculum is comprises one or more reflected plates. These extremely perceptive observations were superbly illustrated (Evitt 1961c, plates 1–9), and were made at a time when the life cycle of dinoflagellate cysts was not well understood. Given the profound nature of these discoveries, it could be argued that this, only the second of Bill's 48 publications on marine palynology, was his finest hour. Bill himself considered that his key breakthrough was Evitt (1961c), and that his subsequent career was simply ‘filling in the details’ (Leffingwell & Damassa 2004). It certainly was a major watershed in the history of study of the dinoflagellate fossil record.

Two years later, just after Bill had left Carter Oil/ Jersey Production Research for Stanford University, he published two short works of very high significance. The main achievements of Evitt (1963a, 1963b) were the beginning of Bill's mastery of dinoflagellate cyst morphology and certain taxonomic actions, the most significant of which was the formal establishment of the acritarchs. This group was erected to accommodate the hystrichospheres which are not dinoflagellate cysts, and other forms with obscure affinities. The acritarchs were subsequently subdivided into 13 subgroups by Downie et al. (1963). Evitt & Davidson (1964) was akin to Evitt (1961c) in impact. These authors helped establish the cyst-producing dinoflagellate life cycle by illustrating a sporopollenin chorate resting cyst inside a motile cellulosic theca (Plate 11; Evitt & Davidson 1964, pl. 1, figs 10, 11). This observation from modern plankton samples confirmed the cyst-theca relationship hypothesised earlier in Evitt (1963a, 1963b).

Bill's virtuosity with dinoflagellate cysts was further demonstrated throughout the rest of the 1960s and early—mid 1970s. Evitt (1967c) is a major work on the archaeopyle which was sumptuously illustrated. Bill collaborated with David Wall who, together with Barrie Dale, also did early pioneering work on the dinoflagellate life cycle. The Evitt and Wall team produced two landmark papers, on Peridinium limbatum and the family Ceratiaceae (Evitt & Wall 1968; Wall & Evitt 1975). Evitt (1970a) was an important review paper, which in effect was an update and expansion of Evitt (1961c). Bill was the guiding force of a forum on dinoflagellates held in 1973, and published as Evitt (1975d). At this time, Bill and Lew Stover undertook a major review of all dinoflagellate cyst genera and their constituent species. Such a massive compilatory task had never been attempted previously, and culminated in Stover & Evitt (1978), which is reviewed in detail in subsection 9.5.

In the 1980s and 1990s, Bill continued his research on the morphology of dinoflagellate cysts. The principal outputs were a textbook (Evitt 1985) and definitive works on the genera Nannoceratopsis and Palaeoperidinium (Piel & Evitt 1980a; Evitt et al. 1998 respectively). Evitt (1985) is documented in detail in subsection 9.6. Piel & Evitt (1980a) demonstrated the intricate epicystal tabulation and the unique cingular archaeopyle of the intruiging Jurassic genus Nannoceratopsis (Plate 13). Evitt et al. (1998) was the long-awaited culmination of his long-held fascination with the genus Palaeoperidinium, especially Palaeoperidinium pyrophorum. This work was truly groundbreaking in that the authors used new techniques in order to prove that the outer cyst wall in this genus was formed outside the theca (Appendix 3). Bill persistently mentioned the fact that not all motile dinoflagellates produce resistant resting cysts, and that this fact constrained some interpretations of the fossil record. This was encapsulated concisely in a short article (Evitt 1981a), and is discussed in subsection 9.4 below.

As befits a major researcher, there have been several dinoflagellate cyst and acritarch taxa named in honour of Bill. These are the dinoflagellate cyst genera Evittodinium (type: Evittodinium giselae), Evittosphaerula (type: Evittosphaerula paratabulata) and Wrevittia (type: Wrevittia helicoidea), and the acritarch genus Evittia (type: Evittia sommeri). Seven dinoflagellate cyst species have been named after Bill. These are Alisogymnium evittii, Evansia evittii, Ginginodinium evittii, Komewuia evittii, Polygonifera evittii, Tehamadinium evittii and Trithyrodinium evittii (see Lentin & Williams 1989, p. 17). In addition, the Silurian acritarch Tunisphaeridium evittii was named after Bill by Cramer (1968). The latter taxon was, however, deemed to be a junior synonym of Tunisphaeridium parvum by Eisenack et al. (1973, p. 1055).

Bill felt that his principal contributions on dinoflagellates were the discovery that fossil forms represented the cyst stage, and his research on dinoflagellate cyst morphology. He thought that future studies would be on the elucidation of dinoflagellate phylogenies using DNA, ecology and palaeobiology (Leffingwell & Damassa 2004); this perceptive forward look has absolutely proved to be the case.

9.4. The selectivity of the dinoflagellate cyst fossil record

Some major groups of dinoflagellates apparently switch on and off the ability to produce preservadle resting cysts as part of their life cycle. This phenomenon means that the dinoflagellate fossil record is potentially significantly biased, over and above any preservation and taphonomic factors which can affect even the most resilient fossils. Bill went to great pains to stress the selectivity of the dinoflagellate cyst fossil record (e.g. Evitt 1981a, 1981b, 1985, p. 37–42).

Evidence from cytological and molecular sequencing studies (Knoll 1993; Fensome et al. 1996a; Medlin & Fensome 2013) indicates that dinoflagellates are relatively primitive, and thus may have originated as early as the Neoproterozoic (∼700 Ma) or Early Palaeozoic (∼500 Ma). This is consistent with data from dinoflagellate biomarkers (Moldowan et al. 1996, 2001; Moldowan & Talyzina 1998). However, the first unequivocal fossil dinoflagellates are Middle Triassic (Helby et al. 1987; Riding et al. 2010). This means that pre-Triassic dinoflagellates either did not make preservable cysts, and/or were represented by certain acritarchs (Dale 1967, 1978; Lister, 1970; Rasul 1974; Miller 1987; Colbath and Grenfell 1995; Playford 2003). The enigmatic Early Palaeozoic (Late Silurian) palynomorph genus Arpylorus was, for a long time, considered to be a dinoflagellate cyst (Sarjeant 1978). However, this genus was recently demonstrated to have possible relationships with the arthropods or the eurypterids, and hence has no dinoflagellate affinity (Le Hérissé et al. 2012).

It is estimated that only around 15–20% of the approximately 2400 known living dinoflagellate species produce fossilisable resting cysts (Head 1996; Gómez 2012). This ratio is an average and is not ecologically consistent. For example, there are relatively few cyst species produced by the diverse dinoflagellate floras in modern tropical environments. By contrast, contemporary shallow-water settings at higher latitudes are characterised by low thecate dinoflagellate diversities, but many of these are cyst-producers (Dale 1976; Wall et al. 1977). There is no known reliable method of determining whether the present low ratio of non cystproducers to cyst-producers is typical of the geological past. The consequence of all this is that the selectivity of the dinoflagellate fossil record means that dinoflagellate cysts are probably a significant under-representation of the entire dinoflagellate record. This should always be borne in mind when interpretating fossil dinoflagellate data. Because of the relative incompleteness of the fossil record, dinoflagellate cysts should not be used as direct proxies for biodiversity and bioproductivity in the same way that, for example, calcareous nannofossils and planktonic foraminifera are. Similarly, they should be used with appropriate caution when analysing, for example, atmospheric and oceanic perturbations, rates of evolution and fluctuations in levels of photosynthesis. However, it should be pointed out that all calcareous fossils are relatively susceptible to pre-, syn- and post-diagenetic dissolution, unlike organic-walled dinoflagellate cysts.

Furthermore, the materials used to construct the dinoflagellate cyst wall are somewhat varied; not all dinoflagellate cysts are organic-walled. Some taxa have mineralised outer layers; there is a relatively diverse group of extant calcareous dinoflagellate cysts and sparse siliceous fossil forms (Figure 21). The calcareous dinoflagellate cysts are extant, emerged during the Late Triassic, and diversified in the Early Cretaceous (Streng et al. 2004). These are all in the peridinioid family Calciodinelliodeae (e.g. Keupp 1984, 1987, 1991; Willems 1988; Keupp & Versteegh 1989). There are only two unequivocal genera of non-endoskeletal siliceous dinoflagellates, both of which are confined to the Palaeogene (Deflandre 1933; Lefèvre 1933a, 1933b; Vozzhenikova 1963). One siliceous genus, Lithoperidinium, is a dinoflagellate cyst; by contrast, the other one, Peridinites, represents the remains of motile thecate cells (Harding & Lewis 1994).

However, perhaps the most significant factor here is the disjunct temporal distribution of certain dinoflagellate taxa. The apparently selective stratigraphical ranges of certain organic dinoflagellate cyst groups are discussed below. Bill mentioned the selectivity of the dinoflagellate fossil record in his first paper on palynology. In Evitt (1961b), he commented that the Jurassic (Pliensbachian—Kimmeridgian) dinoflagellate cyst genus Nannoceratopsis is similar in overall morphology to the modern genus Dinophysis, and hence appears to be closely related. The living representatives of the subclass Dinophysiphycidae do not produce preservadle resting cysts, and Nannoceratopsis is confined to the Jurassic (Figure 21). Much later, Piel & Evitt (1980a) determined that the tabulation of Nannoceratopsis is reminiscent of the orders Dinophysiales and Gonyaulacales because the epicystal tabulation is peridiniphycidalean, and appears to have gonyaulacacean affinities (Plate 12). Because of this, Nannoceratopsis was placed in the monogeneric Order Nannoceratopsiales of the subclass Dinophysiphycidae by Piel & Evitt (1980a). Therefore, Dinophysis and Nannoceratopsis are in the same subclass, but their relationship is somewhat more distant than originally envisaged by Evitt (1961b). Hence it is possible that Nannoceratopsis is an extinct offshoot of the early representatives of the Dinophysiphycidae, and therefore does not necessarily represent a selective phase of cyst production of dinophysialean forms. One of the best examples of the disjunct and selective nature of the dinoflagellate fossil record is the family Ceratiaceae. These distinctive forms with three, four or five horns were present in the Mesozoic, from the latest Jurassic to the latest Cretaceous, and were relatively diverse thoughout much of the Early Cretaceous (Figure 21; Wall & Evitt 1975; Bint 1986; Helby 1987; Monteil 1991; Riding et al. 2000). By contrast, they were entirely absent throughout the Palaeogene and Neogene, but numerous (> 100 species) non-cyst producing representatives are present today both in freshwater and marine settings (Wall & Evitt 1975). This apparent gap of ∼66 My between the end of the fossil record and the modern thecate representatives strongly implies that these forms ceased producing resting cysts during the latest Cretaceous. However, it seems likely that at least some of the range tops of species in genera such as Muderongia, Odontochitina, Phoberocysta, Pseudoceratium and Xenascus represent genuine extinction events. The diversity of the Family Ceratiaceae declined significantly during the Campanian and Maastrichtian. The youngest representatives (e.g. Odontochitina operculata) have Campanian—Maastrichtian range tops (Helby et al. 1987, fig. 40; Crame et al. 1991; Pirrie et al. 1991, 1997; Costa & Davey 1992, fig. 3.9; Roncaglia et al. 1999). Their apparent extinctions may have been related to late Maastrichtian cooling (Bowman et al. 2013), but were apparently entirely unrelated to the Cretaceous/Palaeogene boundary event.

Dinogymnium is a Cretaceous genus, being especially characteristic of the Late Cretaceous interval (Evitt et al. 1967). It is acavate and biconical, and typically has longitudinal folds, an apical archaeopyle and wall canals (Plate 6, figures 5, 6, 8, 9). The latter feature appears to indicate that it is a thecate fossil genus (May 1976, 1977). Dinogymnium is extremely similar in morphology to the modem unarmoured thecate genus Gymnodinium. Although some living species of Gymnodinium, such as Gymnodinium catenatum, apparently produce resistant cysts (Anderson et al. 1988), the Palaeogene to Pleistocene fossil record is devoid of gymnodinioid forms. Therefore, there is a significant stratigraphical gap in the gymnodinioid lineage between the Late Cretaceous and Holocene (Figure 21).

Another example of selectivity is the Palaeogene (Thanetian—Rupelian) cavate peridiniacean subfamily Wetzelielloideae (Figure 21). Representatives of this group are characterised by a four-sided (quadra), rather than a six-sided (hexa), 2a plate (Williams et al. 2015, fig. 1). The quadra 2a plate, and the para ventral arrangement, helps define the subfamily Wetzelielloideae, whereas most fossil and modern taxa in the family Peridiniaceae have hexa 2a plates (Bujak & Davies 1983; Fensome et al. 1993). However, living species of the genus Protoperidinium, which are comparable to Wetzeliella and its relatives, also have quadra 2a plates. The question remains, is the Thanetian to Rupelian range of cavate dinoflagellate cysts referable to the subfamily Wetzelielloideae the true temporal extent of this group, or does this interval simply represent a phase when they produced resting cysts? Evitt (1985, p. 38–39) gave a more wide-ranging review of the selectivity of the fossil record of dinoflagellate cysts related to modern Protoperidinium.

Figure 21.

The species diversity of the organic dinoflagellate cyst fossil record with the ranges of certain genera and groups plotted in order to attempt to illustrate examples of selectivity. The overall numbers of organic-walled species are plotted on the horizontal axis; these data were taken from MacRae et al. (1996, table 1). Six different dinoflagellate cyst groups are illustrated. These comprise four groups of sporopollenin forms, together with calcareous and siliceous dinoflagellates. The geochronological ages were taken from Gradstein et al. (2012).

N — The unusual Jurassic genus Nannoceratopsis; the range of this, which is most diverse in the Toarcian and Aalenian, is Late Pliensbachian to earliest Kimmeridgian in Europe (Riding & Thomas 1992). There are presently 17 validly described species of Nannoceratopsis (see Fensome & Williams 2004, p. 449–451). Nannoceratopsis is somewhat reminiscent of the modern dinoflagellate genus Dinophysis (order Dinophysiales) which does not produce preservable resting cysts (Piel & Evitt 1980a). Ce — Dinoflagellate cysts referable to the family Ceratiaceae. There are 11 unequivocal ceratioid genera which range from the latest Jurassic (Tithonian) to the latest Cretaceous (Maastrichtian). There are 114 species of fossil ceratioid dinoflagellate cysts according to Fensome & Williams (2004). These are as follows: Aptea (two); Balmula (four); Endoceratium (five); Muderongia (18); Nyktericysta (13); Odontochitina (18); Odontochitinopsis (two); Phoberocysta (three); Pseudoceratium (22); Vesperopsis (13); and Xenascus (14). None of these three- to five-horned genera are present in the Palaeogene and Neogene; however, abundant and diverse nonpreservable resting cyst-producing representatives are present today in freshwater and marine environments (Wall & Evitt 1975). D — The genus Dinogymnium (and the closely related genus Alisogymnium). These distinctive forms, which appear to represent dinoflagellate motile forms due to the presence of wall canals (May 1976, 1977; Evitt 1985), are confined to the Late Cretaceous (Turonian to Maastrichtian) interval (Evitt et al. 1967; Wilson & Clowes, 1980, p. 36; Costa & Davey 1992). However, there are isolated reports of Dinogymnium from the Early Cretaceous (Londeix et al. 1996). There are currently eight and 29 valid species of Alisogymnium and Dinogymnium, respectively (Fensome & Williams 2004, p. 37–38, 209–213). These two fossil genera are morphologically similar to the modern unarmoured genus Gymnodinium. The Palaeogene to Pleistocene interval entirely lacks gymnodinioid forms, although some living Gymnodinium species produce preservable cysts as part of their life cycle. W — Dinoflagellate cysts referable to the subfamily Wetzelielloideae. The Wetzeliella group is entirely cavate and comprises 21 genera and 126 species which are confined to the latest Paleocene (late Thanetian) to Oligocene (Rupelian) interval. This plexus is most diverse in the Eocene. The members of this complex all have a four-sided (quadra) 2a plate and have para ventral arrangements (Bujak & Davies 1983, fig. 13; Williams et al. 2015, fig. 1). Most other taxa in the extant family Peridiniaceae have hexa 2a plates (Bujak & Davies 1983). Modern forms of the similar, but acavate, genus Protoperidinium exhibit quadra 2a plates, but only < 5% of the species in this important genus produce geologically preservable resting cysts (Bujak & Davies 1983, p. 43). Most Protoperidinium cysts exhibit ortho-style ventral tabulation. It is therefore not clear whether or not the Thanetian to Rupelian range of the subfamily Wetzelielloideae is the authentic range of this group. Ca — Calcareous dinoflagellate cysts (subfamily Calciodinelliodeae). Modern representatives of this important extant peridiniacean subfamily are entirely autotrophic and marine, and their fossil counterparts are assumed to have had the same life strategy. The cyst wall of the Calciodinelliodeae includes a robust calcareous layer which is prone to fossilisation (Wall & Dale 1968b). This subfamily originated during the Late Trias sic (Early Carnian), where it is largely represented by crypto tabulate forms (Janofske 1992; Streng et al. 2004; Gottschling et al. 2005). The Late Trias sic floras are relatively sparse, and there are no records whatsoever from the Hettangian to the Bathonian. This represents the entire Early Jurassic and most of the Middle Jurassic, an interval of c. 35 My. It is not certain whether this hiatus is genuine, or whether it reflects a lack of investigation and/or unsuitable facies. Calcareous dinoflagellate cysts reappeared in the Callovian, before diversifying markedly in the Early Cretaceous (Keupp & Ilg 1989; Streng et al. 2004, fig. 14.1). They were most diverse during the Cretaceous to Early Palaeogene interval (e.g. Keupp 1991; Kohring 1993; Willems 1994), and the major diversification was during the Hauterivian (Streng et al. 2004, fig. 14.1). This means that the diversity record of calcareous dinoflagellate cysts closely mirrors that of their organic-walled counterparts. S — Non-endoskeletal siliceous dinoflagellate cysts and thecae. These forms represent the fossil peridiniacean subfamily Lithoperidinioideae. This comprises two genera, i.e. Lithoperidinium (a cyst genus comprising seven species) and Peridinites (a fossil thecal genus with three species), which are confined to the Palaeogene (Eocene to Early Oligocene) (Vozzhennikova 1963; Fensome et al. 1993, p. 137–138; Harding & Lewis 1994).

Bill mentioned the selectivity of the dinoflagellate fossil record repeatedly (Appendix 3), and Evitt (1981a) was entirely devoted to this topic. Bill privately commented (personal communication to JBR) that his zeal in emphasising this aspect of the fossil record was largely as a result of compiled dinoflagellate cyst data being used as a proxy for primary productivity in the geological past (e.g. Tappan & Loeblich 1973). It is indeed intriguing that dinoflagellate cysts were produced by certain taxa during specific intervals. The fact that the fossil dinoflagellate cyst record represents a relatively small proportion of the entirety of the Triassic to Pleistocene dinoflagellate spectrum significantly constrains our use of the fossil record. For example, the overall dinoflagellate population density cannot be determined from an association of fossil dinoflagellate cysts, dinoflagellate bioproductivity cannot be meaningfully assessed from the fossil record and the range of a particular pre-Holocene lineage cannot be unequivocally derived from its stratigraphical range.

This Evittian paradigm is a somewhat cautious approach, but nonetheless is extremely insightful. However, despite Bill's misgivings about the completeness of the dinoflagellate fossil record, Fensome et al. (1996b) commented that the Mesozoic and Cenozoic fossil record exhibits significant phylogenetic continuity, and that the Early Mesozoic radiation is a true evolutionary event as opposed to being a preservational artefact. For example, major groups such as the family Gonyaulacaceae appear to have emerged globally due to a genuine evolutionary radiation during the Middle Jurassic, and are extant (Feist-Burkhardt & Monteil 1997; Mantle & Riding 2012). Similarly, the decline in diversity during the Neogene appears to be a direct reaction to declining global temperatures and sea levels (Bujak & Williams 1979; Fensome et al. 1996b). Similarly, while cautioning against what he termed ‘megathinking’ using the dinoflagellate cyst record, Bill admitted that certain evolutionary studies based on fossil dinoflagellate cysts are valid. These are studies at the genus/species level that document changes in local stratigraphical successions over relatively small time slices (e.g. Eaton 1971; Habib 1973; Bujak 1976, 1979; Fensome 1981; Riding & Helby 2001; Riding & Fensome 2002).

9.5. The first ‘Blue Book’: Analyses of pre-Pleistocene organic-walled dinoflagellates — Stover & Evitt (1978)

During the mid 1970s, Lew Stover and Bill Evitt embarked on their only major collaborative project, which was published as Stover & Evitt (1978). This was the first of two ‘Blue Books’ that Bill was involved with (subsection 9.6). The only other collaborations which included Bill and Lew were two relatively short papers (Evitt et al, 1977, 1979). Stover & Evitt (1978) was published by Stanford University and aimed to stabilise the nomenclature and taxonomy of pre-Quaternary organic dinoflagellate cysts. The number of research papers on fossil dinoflagellates had increased exponentially during the 1960s and 1970s. Consequently, numerous taxonomic problems had arisen, and a major overview was well overdue.

Stover & Evitt (1978) gave comprehensive summaries of 279 dinoflagellate cyst genera, including a synopsis, description and comparison (but unfortunately no illustrations), in the main part of this softcover book. It is one of the most important reference works on dinoflagellate cysts ever published and is still used today despite its relatively venerable age, similar to the earlier major works by Davey et al. (1966, 1969). The overall impact of Stover & Evitt (1978) is similar to that of the ‘Lentin and Williams’ indexes of dinoflagellate cyst genera and species (e.g. Fensome & Williams 2004). Stover & Evitt (1978) is a comprehensive (300 pages) systematic analysis of pre-Pleistocene organic dinoflagellate cysts; it was prompted by the belief of both authors that many generic descriptions in the literature were somewhat incomplete and vague. This lack of quality was perceived to be at least partially due to the extremely rapid expansion of research on this topic between the mid 1960s and the mid 1970s. Hence, the principal aims of Stover & Evitt (1978) were to recast generic concepts in a uniform format, and to clearly define new criteria and limits so that any overlapping taxonomic concepts were eliminated. The review that was undertaken by Stover & Evitt (1978) led to many emended genera, and the reattribution of large numbers of species. Wherever possible, existing taxa were maintained irrespective of the level of clarification required. Issues pertaining to taxonomic levels above the genus level were not undertaken. Of the 279 genera considered, 17 were new. It was found that several genera could be suppressed, largely due to them being junior synonyms of older taxa. For each genus, all of the constituent species were treated. Furthermore, the book established three new dinoflagellate cyst species. Bill and Lew had much control over the format and appearance of the book because it was issued by Stanford University Publications. An update of Stover & Evitt (1978) was issued nine years later by Stover & Williams (1987), which included all 84 valid genera published between 1977 and 1985. Stover & Williams (1987) also included a line drawing for the majority of these genera.

The modus operandi of Stover & Evitt (1978) was discussed in the first main chapter (‘Procedures and considerations’, p. 3–9). This described the format for the generic analyses, and defined several key descriptors. For example small, intermediate and large dinoflagellate cysts were defined as having maximum dimensions of < 50 µm, 50–100 µm and > 100 µm, respectively. The descriptive terminology used was clarified here, and concentrated on archaeopyles and opercula, cyst organisation (cavation), and shape.

The main section of the book (p. 11–241) was entitled ‘Analyses of dinoflagellate genera’. It was subdivided into five sections based entirely upon archaeopyle type where known, rather than using a suprageneric classification. These five subchapters are on apical, combination, intercalary and precingular archaeopyles, with the final subdivision (‘other genera’) being on 33 genera where either the forms apparently lack an archaeopyle or the mode of excystment was unknown. This section includes the genus Tuberculodinium, which was considered to have an antapical archaeopyle by Stover & Evitt (1978, p. 240). However, this archaeopyle has more recently been interpreted as being of compound epicystal type by Matsuoka et al. (1998). The majority (61%) of dinoflagellate cyst genera known at that time have apical or precingular archaeopyles. In each of the five sections, the genera were arranged alphabetically. The original description was given (translated into English where appropriate), prior to a one-paragraph synopsis which aimed to concisely summarise the essential characters of the genus. Next, a ‘modified description’ was presented; this provides descriptions of the eight key features of each genus, namely shape, wall relationships, wall features, tabulation, archaeopyle, cingulum, sulcus and size. Each genus was briefly compared to similar genera, then the type was given followed by the other constituent species. The constituent species were subdivided, as appropriate, into accepted species, provisionally accepted species, problematical species and reattributed species. This breakdown is a very useful guide as to the status of a species. Provisionally accepted species have a question mark following the generic name; they do not unequivocally belong to the respective genus and the relevant issues were briefly noted. Problematic species have quotation marks around the generic name, and are even less securely assigned to the genus. They probably do not belong to the respective genus, and it was normally recommended that these taxa should be confined to the type specimens only. Reattributed species are, of course, taxa which were recombined into other genera.

Following the references (p. 243–257), 10 appendices were included in Stover & Evitt (1978, p. 259–287). The subject matter of these appendices is extremely diverse. The first of these, Appendix A (p. 259–264), listed all of the taxonomic departures from Lentin & Williams (1977). The latter work was the second edition of an index of dinoflagellate cyst genera and species. Clearly, this was a major compilation on this palynomorph group and also made taxonomic changes, so it was appropriate that Stover & Evitt (1978) listed any differences from Lentin & Williams (1977) such as species reallocations.

Appendices B (p. 265) and C (p. 266) pertain to Tasch (1963) and Tasch et al. (1964), respectively. Bill concluded in Appendix B that the Permian material from Kansas of Tasch (1963) represents mineral grains (probably gypsum) and specimens of the trilete spore genus Raistrickia. He also contributed Appendix C, which was a brief restudy of the aquatic palynomorphs described from the Lower Cretaceous (Albian) of Kansas by Tasch et al. (1964). Bill found that the majority of the new species described by Tasch in Tasch et al. (1964) have significant problems. Many of the types are poorly preserved, and most of the new species are based solely on single specimens. Fifteen of these new taxa are nonspecific, and were consolidated as Kiokansium unitub er culatum, which was formally described in Appendix D (Stover & Evitt 1978, p. 267–268). Bill was very intrigued by the assemblages that Tasch et al. (1964) reported from the Albian of Kansas. He later suggested to one of his graduate students, Anthony M. Bint, that this material should be recollected and used for a PhD thesis (Bint 1984).

Appendix E (p. 269–270) was a brief review of archaeopyle variability. Certain genera such as Diphyes and Lingulodinium appear to exhibit different archaeopyle styles, which clearly has implications for the integrity of this feature as a generic criterion.

A perceptive and highly influential review of the Gonyaulacysta complex was presented as Appendix F (p. 271–297). This is a wide-ranging synthesis of this major group, and the style of detailed morphological analysis was followed in Evitt (1985). The key characteristics of 18 gonyaulacacean genera were summarised (Stover & Evitt 1978, table 5). Two pairs of genera (Gonyaulacysta and Rhynchodiniopsis, and Impagidinium and Leptodinium) were compared and discussed in detail. The use of details of tabulation to distinguish genera was somewhat controversial at first, but eventually became a standard criterion for distinguishing genera and the higher levels of classification, especially in the gonyaulacaceans (Fensome et al. 1993).

Appendix G (p. 280–281) is a brief assessment of the genera Herendeenia and Omatia, and the seven genera in the Lanternosphaeridium complex were summarised in Appendix H (p. 282). The principal morphological features of the several genera in the very important and closely related Spiniferites complex were outlined in Appendix I (p. 283–284). This topic was further explored in Evitt (1978a).

The final section, Appendix J (p. 285–287), is a concise and highly influential review of the peridiniacean genera. It included a summary of the principal morphological features of 24 genera, which were subdivided into three categories (Stover & Evitt 1978, table 6). The final section of the entire book (Stover & Evitt 1978, p. 289–298) is an alphabetical listing and index of the dinoflagellate cyst genera with archaeopyle group assignments. This section is very helpful in navigating the main section of the book.

It is clear that Lew Stover and Bill put a massive amount of work into this hugely ambitious project. Amassing all the literature and critically evaluating each genus and species, in addition to all the associated microscope work, was a colossal task. Lucy E. Edwards, now of the USGS, worked under Lew Stover as an Exxon Production Research student summer intern while the book was being researched and written in 1974. She recalls that Bill also sporadically worked at Exxon as a consultant, and that he had maintained the index card file of dinoflagellate cysts that was used for Stover & Evitt (1978) since his days at the Jersey Production Research Company (section 5). The principal task undertaken by Lucy Edwards was to work on the card index, and to ensure that each genus had a unique set of the requisite descriptors. This system made synonymous genera easy to identify. Furthermore, Lucy recalls that Lew Stover had already amassed the entire literature on pre-Quaternary dinoflagellate cysts, including copies and translations of many publications not originally written in English. Despite this, Bill and Lew did not need to refer to the literature as, according to Lucy, they had all the genera and species in their heads. However, notwithstanding this encyclopaedic knowledge, they meticulously rechecked all the details when compiling Stover & Evitt (1978).

Bill and Lew's sterling efforts were rewarded by the final product which was a very well-received and extensively used book among all workers on aquatic palynology. It is still an enduring reference text, (at the time of writing) 37 years since it was first published. Stover & Evitt (1978) was, deservedly, one of the best sellers of Stanford University Publications (Geological Sciences), but unfortunately it is currently out of print. It is clear that other researchers were working on similar projects during the late 1970s. Artzner et al. (1979) is a guide to organic dinoflagellate cyst genera organised into 33 families plus incertae sedis. A total of 276 genera were reviewed by Artzner et al. (1979); the main part comprises line drawings of the types of these genera within the 33 families considered. Wilson & Clowes (1980) is another guide to dinoflagellate cyst genera. This includes an alphabetical listing of 330 genera, each with a line drawing and brief details. Wilson & Clowes (1980) was designed so that the pages can be cut up into index cards. The stratigraphical extents of the genera were given in six range charts. Perhaps the most useful features are the line drawings of the types of each genus arranged by five archaeopyle types (Wilson & Clowes, 1980, figs 1–412). The illustrated generic guides of Artzner et al. (1979), Wilson & Clowes (1980) and Stover & Williams (1987) can all be used to help assign dinoflagellate cyst specimens to the most appropriate genus.

9.6. The second ‘Blue Book’: Sporopollenin dinoflagellate cysts — their morphology and interpretation — Evitt (1985)

9.6.1. Introduction

Bill Evitt's magnum opus was undoubtedly his seminal textbook on dinoflagellate cyst morphology, which he had been working on for many years. Evitt (1985) draws on Bill’s morphological research over his entire career in palynology, which started in the mid 1950s. The project came to fruition in the summer of 1985 when Sporopollenin dinoflagellate cysts — their morphology and interpretation was published by the AASP Foundation. It was an immediate classic, and its striking blue cover (Figure 22) gave it the colloquial name of the ‘Blue Bible’ or the ‘Blue Book’. This volume was effectively launched at the Third International Conference on Modern and Fossil Dinoflagellates (Dino 3) at Royal Holloway and Bedford New College, Egham, Surrey, United Kingdom, in August 1985 (Head & Harland 2013). The book had been published several weeks prior to Dino 3, and Bill gave a keynote address on the first day of this symposium. Probably, most of the 140 participants of Dino 3 bought a copy. The principal subject matter of this textbook was presaged by a talk given during 1983 (Helenes et al. 1984).

The writing of Evitt (1985) brought Bill into contact with computers for the first time. The book was written in its entirety on a Wang word processor, and Bill really appreciated the ease of writing and editing that came with digital media. The final manuscript was sent to Bob Clarke, the AASP Foundation production editor, on a disc. This was the first time that Bill had delivered a manuscript which was not on paper. Soon after he finished writing the manuscript in 1984, Bill bought one of the early Apple/Macintosh personal computers for the Stanford University palynology laboratory. Bob Clarke recalls that he met with Bill twice to discuss the book (personal communication to JBR). These were short meetings to finalise various aspects pertaining to production of this book. Bill chose the cover style, the fonts, the two-column format and the type of binding. It was decided to go for the best quality possible due to the importance of this publication.

Evitt (1985) is the only textbook on dinoflagellate cysts in existence, the main subject matter being morphology and tabulation, which were Bill's major research interests. Aspects such as classification and evolution were treated relatively briefly, and there is virtually nothing on biostratigraphy, palaeoecology or geographical distributions. It is a beautifully produced hardcover book of 333 pages, and all of the topics explored were treated authoritatively and comprehensively. Bill began planning the book during the early 1970s. He could see a time in the future when he would retire, and he wanted to expand and formally publish material which he had initially produced for his dinoflagellate cyst short courses. The starting point for Evitt (1985) was the second edition of the course manual for his Teaching Conferences on Fossil Dinoflagellates (section 10). The book is an updated and very much expanded version of these unpublished course notes.

However, the principal impetus which spurred Bill to complete this major project were the new ideas on dinoflagellate tabulation of F.J.R. ‘Max’ Taylor of the University of British Columbia, Vancouver, Canada. Bill first learned about these new concepts in Norway during the summer of 1976, and discussed them with colleagues at Stanford University afterwards (section 10). Thus the majority of the text of Evitt (1985) was written between 1978 and 1983, and this huge effort took up most of Bill's research and personal time during this period. The most protracted phase of work on the book was undertaken during the 1978–1979 academic year, when Bill was given sabbatical leave from Stanford University. Bill commented that the writing proceeded slowly, and that he had badly underestimated the time needed to complete such a large project. He found that he had to recast sections when important new papers were published. For example, Bill rewrote the section on tabulation patterns because he was so strongly influenced by Taylor's ideas on this topic. These were published in biological journals (e.g. Taylor 1978, 1980), and Bill adapted these theories to fossil dinoflagellates over several iterations.

Figure 22.

The front cover of Bill Evitt's major textbook Sporopollenin dinoflagellate cysts - their morphology and interpretation, published during the summer of 1985 by the AASP Foundation (Evitt 1985) (subsection 9.6). Its vibrant blue colour quickly gave it the nicknames the ‘Blue Bible’ and the ‘Blue Book’. Note the line drawings of Areoligeral sp. (top left) and Oligosphaeridium abaculum (bottom right), both in dorsal view. The two images are based on Wall & Evitt (1975, pl. 3, fig. 14) and Evitt (1985, fig. 10.2A), and Davey (1979a, fig. 1B; pl. 49, fig. 3) and Evitt (1985, fig. 1.7F) respectively. This image is reproduced with the permission of AASP — The Palynological Society.

Evitt (1985) included exhaustive descriptions of the large diversity of morphological features exhibited by dinoflagellate cysts, and new ideas on tabulation patterns and their interpretations. Bill was similar in many ways to pioneers such as Georges Deflandre and Alfred Eisenack (to whom the volume is dedicated) in that he was not especially interested in biostratigraphy. He preferred instead to concentrate on morphology, while working on exceptionally well-preserved material. A principal strand of this text is a description of a new tabulation scheme, now known as the ‘Taylor-Evitt System’ which was first proposed by Taylor (1978, 1980). Evitt (1985) was initially subdivided into three parts, namely a general section on dinoflagellates and a section on cyst morphology followed by one on cyst interpretation. These major sections were then further arranged into 13 chapters.

9.6.2. Part II — Morphology of the cyst ( Chapters 3 to 6)

Part II of Evitt (1985, p. 47–145) was entitled ‘Morphology of the cyst’. The introduction set out the criteria for the identification of dinoflagellate cysts. These are: (i) general features such as shape, size and orientation; (ii) wall structure and surface features; (iii) tabulation; and (iv) the archaeopyle. This section is concerned virtually exclusively with the order Peridiniales, especially the relationships between modern thecae and fossil cysts. The four chapters of Part II provide a thorough review of the morphology of dinoflagellate cysts. These are on the organisation of cysts and thecae, the cyst wall, tabulation and the archaeopyle, respectively.

Figure 23.

A diagrammatic depiction of the idealised life cycle of a cyst-producing dinoflagellate. It involves both sexual reproduction and cyst formation. In phase A, the dinoflagellate cells are haploid and mobile schizonts. Phase B illustrates diploid, motile dinoflagellate cells which are planozygotes; the nucleus is indicated by large dots. In phase C, the dinoflagellate cells are diploid and nonmotile hypnozygotes apart from the cell which has excysted on the left. Note the open archaeopyle in the empty cyst on the extreme left in phase C, which represents a potential fossil. This image is modified from Fensome et al. (1996c, fig. 4), and was originally published as Evitt (1985, fig. 1.3).

Chapter 3 (Evitt 1985, p. 49–60) discussed the morphology and organisation of dinoflagellate cysts and thecae. Basic descriptive terms were introduced, and the system of Kofoid (1909) for analysing and labelling thecal tabulation was briefly described. It was Bill's intent to minimise the number of descriptive morphological terms. The shortcomings of the Kofoidian tabulation system with respect to plate homologies were outlined. The term ‘paratabulation’ for the reflected tabulation of dinoflagellate cysts was used throughout. However, this term is not commonly used at present because it should always be obvious whether a dinoflagellate cyst or a theca is being discussed (Norris 1978b, p. 303). The Kofoidian system can be used for the tabulation of dinoflagellate cysts with certain limitations. These are: (i) cyst tabulation is often incompletely expressed; (ii) a variety of cyst features indicate the position and shape of plates; (iii) small thecal plates are unlikely to be expressed on the cyst; (iv) shapes of plates on cysts may differ from their thecal counterparts because cyst and thecal shapes differ; (v) postmortem degradation may affect cysts. Therefore, the cyst tabulation may differ from the precise configuration of plates on the theca. The shape of cysts may also affect the possibility of viewing all areas in a fixed mount, necessitating the manipulation of individual specimens. Dinoflagellate cysts may exhibit significant intraspecific variability; hence, descriptions of species based on small numbers of poorly preserved specimens are of limited value.

Chapter 4 (Evitt 1985, p. 61–79) described the structure of the dinoflagellate cyst wall. Dinoflagellate cysts, particularly proximate forms, may exhibit thecamorphic features. These are items that resemble and correspond to thecal elements, but which are functionless or have a different purpose on the cyst. Other features, particularly the processes of chorate cysts, are cystomorphic in that, although they may be homologs of thecal characters, they are the defining features of the cyst. Cyst walls may be multi-layered, with cavities separating or partly separating the layers. The external relief of a dinoflagellate cyst may comprise a great variety of projections; these include some with distal interconnections that form an additional layer. The morphology, number and orientation of the distal process tips may indicate tabulation. Features may be sutural and/or gonal, intergonal or intratabular. Zones of incremental plate growth in the theca may be represented by pandasutural bands in the cyst. Other features such as claustra and the porichnion may occur. The development and functional morphology of the cyst wall are not well known; however, fossil evidence can limit the possibilities. The theca appears to have at least some role as a template for cyst development. Large processes and other ornament suggest a centripetal sense of development. However, further centrifugal growth of processes and other elements cannot be ruled out, and major restructuring of the cyst wall during its ontogeny may occur.

Chapter 5 described tabulation, which is the principal criterion used to classify and identify thecate dinoflagellates (Evitt 1985, p. 81 – 119). The complete tabulation of a theca can be obtained by dissection of the plates using sodium hypochlorite solution. By contrast, cyst tabulation is frequently expressed partially and variably, if at all. Separation of the plates in cysts is impossible because there are no true sutures between them except for the archaeopyle sutures. A variety of wall features and ornamentation of the cyst reflect thecal tabulation, which can be interpreted by the careful observation of well preserved material.

This account primarily described gonyaulacoid and peridinioid tabulation patterns, which are the two most commonly encountered in fossil cysts. Peridinioid cysts are relatively less diverse in their tabulation patterns than the gonyaulacoids are. Also, the Kofoidian system of plate labelling only rarely leads to nonhomologous plates being given the same label in peridiniacean forms. This Kofoidian system of labelling is therefore adequate, and no new system was proposed for peridinioid patterns. However, for the more complicated and variable tabulation patterns of the gonyaulacoid group, Evitt (1985) modified the plate nomenclatural system first suggested by Taylor (1978, 1980). This is now referred to as the Taylor-Evitt system. The new system more clearly preserves homologies by giving equivalent plates the same label. The traditional Kofoidian tabulation nomenclatural scheme was not being used effectively, so Evitt (1985) developed a new scheme which concentrated on geographical plate homologs, rather than a more rigid and mechanistic plate numbering system.

Four groups of gonyaulacoid tabulation patterns, corniform, partiform, quinqueform and sexiform, were distinguished. These are all theoretically derived from a hypothetical precursor proposed by Taylor (1978, 1980), and modified by Evitt (1985). The four tabulation patterns were described in detail, with both Kofoidian and Taylor-Evitt labelling systems included, and including subdivisions and variations (Evitt 1985, p. 91 – 119). Evitt (1985, p. 117) concluded that cyst tabulation, including that of the sulcus, merits diligent investigation and thorough description, despite the frequent difficulty of study. Immediately following the publication of Evitt (1985), many authors began to provide both Kofoidian and Taylor-Evitt plate labelling systems on line drawings of dinoflagellate cysts (e.g. Dürr 1987, figs 2, 3; Riding 1987, figs 12–14). However, since the mid to late 1980s, the tendency has developed for researchers to use the Kofoidian plate labelling scheme in a strictly disciplined, interpretive and objective way, fully taking into account plate homologs.

Chapter 6 (Evitt 1985, p. 121 – 145) is on the archaeopyle and, as such, is an update of Evitt (1967c). The archaeopyle is the opening in the cyst wall through which the protoplast emerges during excystment. Typically, the archaeopyle is an operculate opening that corresponds to one or more plates, even when no other indication of tabulation is present. It is outlined by the principal archaeopyle suture, a cystomorphic feature that may be reduced or enlarged. Often, some of the tabulation pattern can be interpreted from the archaeopyle and/or the operculum. For example, peridinioid cysts can often be recognised because the archaeopyle consists of the distinctive anterior intercalary plates. Accessory archeopyle sutures, if present, can yield more information on tabulation. Opercula or opercular pieces can be free, adherent or adnate. In peridinioid cavate cysts, there are usually two identical archaeopyles in each wall. By contrast, in cavate gonyaulacoid cysts there are two openings, but there is only one operculum made from endophragm (Eaton 1984). The archaeopyle type can be abbreviated; for example, type P is a monoplacoid archaeopyle formed by the complete release of the area corresponding to a precingular plate. A comprehensive survey of archaeopyle types, and ways of describing them, was given (Evitt 1985, p. 130–144). The taxonomic significance of the archaeopyle was debated. Although many genera and species are currently separated on the basis of archaeopyle type, the number of taxa that include more than one style of archaeopyle is growing. Evitt (1985, p. 145) commented that the use of archaeopyle type at the generic level to separate otherwise similar taxa is inappropriate.

11.1. Introduction

Bill Evitt organised the first ever scientific gathering specifically on dinoflagellates and their cysts. This was a forum on this topic held at Anaheim, California, on 16 October 1973 as part of the Sixth Annual Meeting of the AASP (Figure 25). The symposium comprised six keynote presentations followed by panel discussions on biostratigraphy and other aspects; it was subsequently published as (Evitt 1975d).

Perhaps due to Bill's great success with the 1973 meeting at Anaheim, during the mid 1970s, Graham L. Williams urged Bill and Lew Stover to organise a major conference on both fossil and modern dinoflagellates. Graham Williams was the instigator of the famous ‘Lentin and Williams’ indexes of dinoflagellate cysts (e.g. Fensome & Williams 2004). The ultimate vision of Graham Williams was a gathering designed to unify researchers who shared an interest in this remarkable group of protists. At that time, it was clear that fossil specialists knew little about the biology of modern dinoflagellates. Similarly, the biologists did not fully comprehend the scope of the dinoflagellate fossil record. As a consequence of these promptings, Bill, Lew and Karen Steidinger successfully organised such a meeting in 1978. This symposium was such a great success that similar conferences, informally termed the ‘Dino meetings’, have been held approximately every four years (Head & Harland 2013).

Figure 25.

A photograph of the team of 10 panellists and speakers at the ‘Forum on Dinoflagellates’ organised by Bill Evitt and held on the first day of the 6th Annual Meeting of the AASP at Anaheim, California. This forum took place on 16 October 1973, and the panel held a discussion on dinoflagellate cyst bio stratigraphy and related topics during the afternoon. The members of the panel are, from left to right: Lewis E. Stover, Warren S. Drugg, Marcel E. Millioud, Graham L. Williams, Geoffrey Norris, David Wall, William A.S. Sarjeant, Bill Evitt, David J. McIntyre and Wayne W. Brideaux. This image is from Evitt (1975d, p. v), and is reproduced with the permission of AASP — The Palynological Society.

11.2. The Penrose Conference on Modern and Fossil Dinoflagellates (1978)

As a direct result of the entreaties of Graham Williams, Bill Evitt, Lew Stover and the biologist Karen A. Steidinger sought financial support from the GSA for a Penrose conference on dinoflagellates. Richard A.F. Penrose, Jr. (1863–1931), a mining geologist and entrepreneur, was very active in and a major benefactor of the GSA, and the Penrose conferences are named after him (Stanley-Brown 1932). The GSA instigated the Penrose conference series in 1969 in order to bring together multidisciplinary groups of earth scientists, to facilitate open discussions of ideas in an informal atmosphere and to stimulate individual and collaborative research with no commitment to publication ( http://www.geosociety.org/penrose).

The GSA agreed to fund this meeting, and the Penrose Conference on Modern and Fossil Dinoflagellates was held at Colorado Springs, Colorado, between 16 and 21 April 1978. The conference was originally due to be held in the Rocky Mountain ski resort of Vail, Colorado, but a highly contagious outbreak of a viral gastric sickness necessitated a change of venue with only a few days’ notice. It was not a fully open meeting; the 68 delegates (including eight students) were a mix of palaeontologists (∼60%) and biologists (∼40%), and were all invited (Figure 26). However, it was apparently possible to request an invitation (personal communication, Lucy E. Edwards to JBR). Most attendees were from North America (56), but 12 delegates from Argentina, Australia and Europe also participated.

Figure 26.

The group photograph taken at the Penrose Conference on Modern and Fossil Dinoflagellates held at Colorado Springs, Colorado, in April 1978. Bill Evitt is seated in the second row from the front, and is the fourth person from the left. He is sporting a ‘Stanford Palynology’ t-shirt with the famous SEM image of Peridinium limbatum, and is flanked by co-organiser Karen Steidinger on his right and Lois Elms on his left. Lew Stover, the other main proponent of the meeting, is sixth from the left on the same row and is clearly enjoying a joke with Lucy Edwards to his left. The names of all participants were given in Head & Harland (2013, p. 4). The image was supplied by Martin Head, and is reproduced with permission.

At this Penrose conference, the two groups, i.e. biologists and geologists, spent a considerable time explaining and defining concepts and terminology in order to ensure mutual understanding before the more formal scientific presentations. Discussions then followed on a very broad range of topics including blooms, classification, ecology, evolution, the fossil record, geographical distributions, life cycles, morphology, the origins of dinoflagellates, plate homologies, plate imbrication patterns, plate labelling, selective preservation, tabulation and taxonomy. There were several keynote presentations by invited speakers, who were given the specific task of communicating to both disciplines. Particularly lengthy discussions took place on the evolution of dinoflagellates, and whether a decrease or an increase in plate numbers with time represented an evolutionary progression (Bujak & Williams 1981). Bill stressed that the dinoflagellate fossil record is profoundly incomplete, and how the disjunct lineages may engender spurious conclusions on aspects such as bioproductivity and evolution (subsection 9.4). Furthermore, Bill noted how the classic Kofoidian plate notation can frequently obscure morphological homologues, and hence evolutionary relationships. Some of the talks at Colorado Springs on plate imbrication patterns represented the first ever discussion of this phenomenon. Also prominent were debates on the role of dinoflagellate cysts in seeding red tides, and the fact that some modern dinoflagellate cysts are, in purely morphological terms, acritarchs.

Sarjeant (1998, p. 8) recalled Geoff Eaton's presentation on the development of dinoflagellate plate patterns, and a talk by Geoff Norris on dinoflagellate evolution. These were later published as Eaton (1980) and Norris (1978a), respectively. It quickly became clear that, in the late 1970s, workers on modern dinoflagellates were largely unaware of the extensive, rich and diverse fossil record of dinoflagellate cysts. Likewise, the geological community was not cognisant of the expansion in knowledge of the morphology of living dinoflagellates, for example the eyespot (Sarjeant 1998, p. 8). This conference was universally deemed to have been a resounding success, and valuable cross-discipline liaisons were made which eventually led to significant collaborations across the two communities. A short report on the meeting was published as Evitt et al. (1979).

11.3. The International Conferences on Modern and Fossil Dinoflagellates (1981 onwards)

The Penrose meeting in 1978 was so successful that the now-united community of dinoflagellate researchers organised similar international unified fossil/modern dinoflagellate conferences approximately every three to five years following the Colorado Springs meeting. The subsequent symposia were open to all interested parties, and the next one was organised by Hans Gocht and Harald Netzel; it was held in Tübingen, Germany, in early September 1981 (Head & Harland 2013, fig. 2). This was playfully entitled the ‘Hexrose meeting’. The tradition was continued further, and these meetings are now colloquially termed the ‘Dino meetings’. At the time of writing, the last one was Dino 10, a joint meeting led and organised by AASP — The Palynological Society, and held in San Francisco, California, during late October 2013 (Clark et al. 2013). The history of the first nine ‘Dino meetings’ was comprehensively documented by Head & Harland (2013). Each one seems to have had an especially memorable aspect. Examples include the wider realisation of the abundance and diversity of calcareous dinoflagellates at the ‘Hexrose meeting’ in 1981, the concept of ‘round brown’ dinoflagellate cysts at Dino 3 (or ‘Heptrose’) in 1985 and the toxic dinoflagellate Pfiesteria piscicida or ‘phantom dinoflagellate’ (Burkholder et al. 1992; Burkholder & Marshall 2012) at Dino 5 in 1993.

Bill attended most of the post-Penrose ‘Dino meetings’. His magnum opus (Evitt 1985) was published only weeks prior to Dino 3 at Egham, Surrey, United Kingdom, in August 1985. Bill gave a keynote talk at this meeting, summarising the new Taylor-Evitt tabulation scheme. The last one he attended was Dino 6 held in Trondheim, Norway, in June 1998, where he was awarded an honorary membership to the Palaeobotanical and Palynological Society of Utrecht (Appendix 1). Bill was wholeheartedly of the view that the ‘Dino meetings’ have, over the years, significantly aided communication between biologists and geologists. Specifically, he felt that the collaboration between the geologist Rob Fensome and the biologist ‘Max’ Taylor, which led to the publication of the unified suprageneric classification of fossil and living dinoflagellates (Fensome et al. 1993), would never have materialised without the galvanising effect of the ‘Dino meetings’. The principal importance of Fensome et al. (1993) is that the community of dinoflagellate researchers are now fully aware of the need for a totally integrated classification scheme.