The anatomy of the petrosal and associated middle ear structures are described and illustrated for the brown rat, Rattus norvegicus (Berkenhout, 1769). Although the middle ear in this iconic mammal has been treated by prior authors, there has not been a comprehensive, well-illustrated contribution using current anatomical terminology. Descriptions are based on specimens from the osteological collections of the Section of Mammals, Carnegie Museum of Natural History, and a CT scanned osteological specimen from the Texas Memorial Museum. The petrosal, ectotympanic, malleus, incus, stapes, and inner ear were segmented from the CT scans.

The petrosal of the brown rat is only loosely attached to the cranium, primarily along its posterior border; it is separated from the basisphenoid, alisphenoid, and squamosal by a large piriform fenestra that transmits various neurovascular structures including the postglenoid vein. The extent of the piriform fenestra broadly exposes the tegmen tympani of the petrosal in lateral view. The floor of the middle ear is formed by the expanded ectotympanic bulla, which is tightly held to the petrosal with five points of contact. The surfaces of the petrosal affording contact with the ectotympanic bulla are the rostral tympanic process, the epitympanic wing, the tegmen tympani, two of the three parts of the caudal tympanic process, and the tympanohyal, with the ectotympanic fused to the last. The ectotympanic in turn is fused to the elongate rostral process of the malleus, which is only discoverable through the study of juvenile specimens. In addition to osteology, the major nerves, arteries, and veins of the petrosal are described and illustrated based on the literature and osteological correlates.

The petrosal of the brown rat is compared with those of several Eocene rodents to put the extant form in the context of early members of the rodent lineage. Comparisons benefitted from CT scans of the middle Eocene ischromyoid Paramys delicatusLeidy, 1871, from the western United States, affording the first description of the endocranial surface of the petrosal in an Eocene rodent. The petrosals in the Eocene fossils are more tightly held in the cranium, but the ectotympanic contacts the petrosal through the same five points, with some modifications. The most unexpected discovery in Paramys delicatus was the presence of a prominent tentorial process of the parietal in contact with the reduced crista petrosa.

Laniifera Hampson is diagnosed and compared to related genera of Asciodini (Crambidae: Spilomelinae). Laniifera rawlinsi, n. sp., is described from the Dominican Republic. The larvae are predicted to feed in Opuntia cacti, as do related taxa.

A new genus and species of a basal synapsid Caseidae, Martensius bromackerensis, is described based on four partial to nearly complete mostly articulated skeletons that provide a comprehensive knowledge of the skeletal morphology. All four specimens were collected from a single site, the Bromacker quarry, in the Lower Permian Artinskian Tambach Formation, Germany. The Bromacker caseid is the first to be reported from Germany and can be easily distinguished from all other caseids based on substantial lists of autapomorphic and plesiomorphic characters. Of the four caseid specimens only the smallest, a juvenile, and the largest, an adult designated as the holotype, are nearly complete, articulated, and possess skull material: in the juvenile a small partially articulated portion of the skull, and in the adult a nearly complete but dorsoventrally crushed skull. The two specimens are distinguished from one another by features attributed to different ontogenetic stages of development, which include skeletal ossification, proportional dimensions of elements, and most interestingly marginal dentitions. The last category includes a feature unique among caseids of an ontogenetic change in the dentition from insectivorous in the juvenile specimen to what is believed to be an omnivorous dentition in the adult.

A phylogenetic analysis posits the Late Pennsylvanian Eocasea martiniReisz and Fröbisch, 2014, as the basalmost member of the monophyletic Caseidae and the later occurring middle Early Permian Bromacker caseid as the sister taxon of the remaining late Early and Middle Permian members of the clade. This series of relationships parallels a proposed chronology of evolutionary changes in the dentitions and associated diets of caseids.

Reproductive characteristics of the Eastern American Toad (Anaxyrus americanus americanus) vary geographically across its broad eastern North American range. Northern populations are known to breed for a shorter period that begins later in the season (April and/or May) than southern populations that can begin in winter and last until April. Delayed maturity and larger minimum body size are also associated with northern populations. Specimens collected during two years of systematic trapping during 1982–1983 at the Powdermill Nature Reserve (PNR), Westmoreland County, Pennsylvania, were examined to test predictions of geographic patterns associated with reproduction and growth of a southwestern Pennsylvania population. The results indicate a short egg laying season in May, large adult body size, and delayed maturity. An apparent response to northern Allegheny climate, the reproductive-related patterns of this population were similar to those of other northern regions rather than populations at similar latitudes within Pennsylvania. Eastern American Toads collected from a breeding site at PNR in 2014 were larger in body size, clutch size, and egg size than those of the 1982–1983 study. Most notably, loss of open breeding habitat in the 30+ years between sampling periods resulted in fewer larger toads producing on average larger eggs and twice the clutch size than counterparts studied during earlier successional series of this study site. These differences quantify geographic and temporal variability in life history traits of an ecologically versatile and geographically widespread species and provide landscape-wide predictions of life history responses by the Eastern American Toad to natural or human-mediated changes to natural areas.