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British Pelagic Tunicates, and the Choice of the 21 Species

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British Pelagic Tunicates, and the Choice of the 21 Species REVIEWS BULLETIN OF MARINE SCIENCE, 34(1): 175-176, 1984 BRITISHPELAGICTUNICATES.J. H. Fraser. Synopses of the British Fauna (New Series) No. 20. Cambridge University Press. 1982. 57 pp., 23 figures, glossary and index. Soft cover. $12.95. The Synopses of the British Fauna, of which this is No. 20 in the series, are designed as field and laboratory pocketbooks for the use of amateur and profes- sional naturalists. They are intended to bridge the gap between popular field guides and professional treatises and monographs. This slim little volume on pelagic tunicates seems to serve this purpose admirably. Each of the 21 species of Appendicularians and Thaliaceans treated in this work is illustrated with line drawings showing the pertinent characters required for identification. Both aggregate and solitary forms are shown when such occur. Descriptions are brief but adequate and there are notes on distribution and abun- dance where pertinent. A very useful account of anatomical structures, life his- tories, ecology and distribution is given for each major group. There is also a glossary, index and a useful list of references. The introduction serves also to inform the reader on methods of capture, preservation and labeling. Complete keys are given for all levels from class to family, genus and species. The author is to be congratulated on the clarity of the couplet definitions. One may be puzzled, however, by the title, British Pelagic Tunicates, and the choice of the 21 species. Under the Appendicularia Fraser states that only Oi- kopleura dioica and Fritillaria borealis are found in British estuaries and inshore waters while Oikopleura labradoriensis is frequent in areas around the British Isles but is unlikely to be found in inshore waters. Likewise O. fusiformis is associated with the influx of oceanic warm water and is only an occasional visitor. But excluded in this same category are 10 other species. Why then is OJusiformis included? In the Thaliacea the genus Doliolum has three species and a variety: D. na- tionalis, D. mullen' (correctly muellen), D. gegenbauri and D. gegenbauri var, tritonis. All are listed as British tunicates yet all are offshore species. One is listed as rarely taken in offshore waters near the British Isles (D. mullen). Among the Salps 12 species are listed: Helicosalpa virgula, Cyclosalpa pin nata, C affinis, C bakeri, Cfoxtoni, Salpafusiformis, Thalia democratica, lhleapunc- tata, lasis zonaria, Thetys vagina, Pegea confoederata and Ritteriella picteti. Their presence in British waters is not documented but some questions are raised. Cyclosalpa foxtoni "has not yet been defintely identified from British waters" while Thetys vagina has been reported only twice, in 1928 and 1958. Ritteriella picteti was taken by HMS CHALLENGERin 1953 southwest of Ireland and has not since been recorded from British (?) waters. Two pyrosomes are given: Pyrosoma spinosum and P. atlanticum giganteum. The first was recorded only once in 1907 from 95 miles southwest ofIreland; the latter has not been recorded since 1933 and is not included in the Plymouth Marine Fauna. The questions raised above would have been avoided if the author had set limits to what are called "British waters." It seems obvious that selections were made on a basis not given in the book. Nevertheless, this is a book that should prove useful to graduate students and others needing a handy, concise introduction to the pelagic tunicates and its 175 176 BULLETI'i OF MARINE SCIENCE. VOL. 34. NO. I. 1984 glossary and anatomical descriptions will be of assistance when consulting more specialized works.- Gilbert L. Voss. Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Causeway, Miami, Florida 33149-1098. BULLETIN OF MARINE SCIENCE, 34( I): 176, 1984 THE SEA FLOOR, AN INTRODUCTION TO MARINE GEOLOGY. E. Seibold and W. H. Berger. Springer- Verlag, Berlin, Heidelberg, New York. 1982. vii + 288 pp. $20.00. The combination of Eugen Seibold and Wolfgang H. Berger as co-authors of an introduction to marine geology must result in an excellent product, and indeed it has. The Sea Floor presents the most important new advances in marine geology in a broad historical context. These topics are introduced with brief lucid dis- cussions, substantive factual information, and clear and adequate illustrations. The organization of the book proceeds from general discussion of the origin and morphology of the ocean basins and their margins, through the sources and composition of marine sediments to discussions ofthe effects of sea level changes, interactions of organisms with the sea floor, the imprint of climate on marine sediments, paleoceanography interpreted from the deep-sea record and finally an account of resources from the ocean floor. Nine useful appendices provide further background information to the reader. The authors are especially effective at introducing the recent work on sediment- organism interactions and new concepts of climate dynamics emerging from pa- leoceanographic studies. The concentration is on the sedimentary record and processes; the oceanic crustal rocks and deep-seated processes are treated only briefly. As an introduction to modern marine geology, this is an excellent book; the authors have done a masterful job of presenting major ideas without getting lost in a welter of details. It will be useful as a textbook for geologists at the under- graduate level. At the graduate level it fills the need for an introduction to marine geology for oceanographers specializing in other disciplines.- William W. Hay, University of Colorado Museum, Campus Box 218, Boulder, Colorado 80309..
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