Robert S. Egan<sup>1,*

1</sup>Department of Biology, University of Nebraska at Omaha, Omaha, NE 68182-0040, U.S.A. e-mail: r

^*The cumulative database for this series is available in searchable form on the World Wide Web at http://www.nhm.uio.no/botanisk/bot-mus/lav/sok_rll.htm. I owe special thanks to Bill Buck for providing copies of papers by other authors, which were otherwise unavailable to me, and to the coöperating authors who send reprints or electronic versions of their works to me for inclusion in this series.