Phycologia (1996) Volume 35 (4),372-373

BOOK REVIEWS

Syllabus der Boden-, Luft- und Flechtenalgen. HANUS ETIL AND GEORG GARTNER. Gustav Fischer Verlag, Stuttgart, Jena, New York, 1995, 721 pp. ISBN 3-437-30777-0. Price D M 198.0010S 1545.00/SFr 190.50.

In an account of the biodiversity of eukaryotic algae, Ander­sen (1992, Biodiversity and Conservation 1: p. 286) noted two areas requiring immediate research. The first of these was un­derstanding the biodiversity of marine phytoplankton. The second was that 'of algae growing on soils, trees and rocks throughout the terrestrial environment'. He then noted that, 'Unfortunately, most phycologists have ignored this area, in large part due to the difficulties in identifying the organisms'. Other recent reviews have made the same point [(e.g. L. Hoff­mann (1989) The Botanical Review 55: 77-105)].

Floras of freshwater algae, although often including taxa that can also be found in terrestrial habitats, invariably do not give a comprehensive treatment of these algae. To be able to make reliable identifications of the species comprising most communities requires access to a large and widely scattered literature. In particular, the frustrating 'unidentifiable round green objects' ('URGOs' !), so frequently encountered in soils, are often dismissed as too difficult to identify. Many of them undoubtedly end up as dubious records of the chlorophytes Chlorococcum humicolum and Chlorella vulgaris. These po­tentially hide a wide diversity of taxa, numbering up to at least 50 of the genera included in this volume by my reck­oning. Without the application of culture techniques, that is the way it will remain.

This huge volume is a very welcome compilation of de­scriptions and mostly high-quality line illustrations taken from the primary literature. Keys are provided to the classes, orders, families and species using characters observed during light microscopy. About 1000 species are included from 260 genera in the 15 classes of eukaryotic algae found in 'aero-terrestris­che' habitats, i.e. associated with soils; with plant, wood, and rock surfaces; and occurring as phycobionts in lichens. Well over half the species are chlorophytes and the majority of the remainder are diatoms or xanthophyceans. The blue-green al­gae (Cyanobacteria) are not presented, the authors noting that these are to be treated in a forthcoming volume of the 'Siiss­wasserflora von Mitteleuropa'.

A short introductory section provides historical background to studies on the systematics of terrestrial algae, defines their habitats and briefly describes their ecology. The importance of using cultures for the study of most taxa other than diatoms is emphasised. Techniques are described for the growth and isolation of both free-living forms and phycobionts.

Each species is provided with a concise but detailed de­scription, an indication of important synonymy, a brief note on its occurrence and citations to literature where illustrations can be found. If cultures are available, reference is made to accession numbers of strains held in major collections, which should remind researchers of the importance of confirming

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their identifications by comparison with authentic strains where they exist. The illustrations, selected and copied from the original publications, are displayed on 214 mostly full­page figures. Uncertain species are also described and often illustrated.

Finally, a glossary explains about 240 terms used in the text. This is aided by 15 plates of line illustrations, especially of typical reproductive structures and life cycles. The exten­sive bibliography of about 500 references ranges from the classical literature of the nineteenth century to studies pub­lished in 1993. The taxonomic index directs the reader to both valid taxa and synonyms.

This state-of-the-art description of the terrestrial algal flora based on light microscopy provides the basis for a resurgence of interest in the ecology of terrestrial algae. The value of many previous studies has been degraded by unreliable iden­tifications. The distribution, microhabitat preferences, abun­dance and productivity of most species remains unknown. No doubt studies of ultrastructure and molecular genetics will in­creasingly lead to revision of our concepts of many of the species and higher taxa included here. However, the light mi­croscope will remain the major tool for many and hence this volume will be an essential companion of researchers in ter­restrial algae for years to come.

Paul Broady, Department of Plant and Microbial Sciences, University of Canterbury, Christchurch 8002, New Zealand.

Freshwater Algae, Their Microscopic World Explored. HILDA CANTER-LuND AND JOHN W.G. LUND. 1995, 360 pp. Biopress Ltd, The Orchard, Clan age Road, Bristol, BS3 2JX England. £49.50 + £4.00 P & p. ($85 + $6 P & p) [Hardcover].

Any freshwater phycologist who picks up Freshwater Algae

and looks inside will be delighted! The photography is out­standing. The book illustrates many of the common freshwater algae as well as some that are rare. The book also includes excellent photographs of protozoa and aquatic fungi that are associated with algae. Except for a few photographs of habi­tats and macroscopic thalli, the entire photographic section is based on light photomicrographs. Never has there been such an extensive and beautiful pictorial treatise of freshwater al­gae.

Freshwater Algae is published with a beautifully illustrated hardcover. The text is printed on high-quality paper so that the photographic reproduction is of highest quality. The bind­ing appears to be of high quality, insuring that the book will stand up to extensive use. The print is easy to read and there are few typographical errors (e.g., occurence, p. 34; flattended, p. 174; eutrophica-tion, p. 224). There are two incorrect state­ments regarding nomenclature. On page 108, the authors state 'The name Xanthophyte should be replaced by Tribophyte to accord with the rules of nomenclature' and on page 166 'The

name Haptophyte has now been replaced by Prymnesiophyte in order to comply with the internationally agreed rules of botanical nomenclature'. The Botanical Code does not require either typification or priority above the family level, and there­fore class names are not so bound-Xanthophyceae and Hap­tophyceae are perfectly acceptable names.

The micrographs cover the major groups of freshwater al­gae but the coverage is uneven. The green algae (73 pp.), diatoms (30 pp.) and blue-green algae (44 pp.) are covered extensively, but others such as the dinoflagellates (10 pp.) and cryptophytes (2 pp.) are treated superficially. The generic treatment is irregular. For example, Cladophora (Figs 118-123) has about five pages of text and figures. Conversely, the authors write 'The largest genus of desmid and of chloro­phytes as a whole is Cosmarium (Figs 44, 45). Over 2000 species have been described'. Nothing more is said: Why such a staggering diversity? What is the range of forms? Do they live in a wide range of habitats? We never learn any more about this largest genus of the green algae.

The text of the book has an almost impossible task of nar­rating a cohesive and logical story around the selected pho­tomicrographs. As a result, the text is occasionally disjunct. The task was made even more daunting by trying to appeal to the lay person who has little or no familiarity with micro­scopic algae. The book may have benefited from a short in­troductory section to aid nonbiologists. Terms like chloroplast (p. 21), pyrenoid (p. 22), nucleus (p. 40) and eyespot (p. 88) are defined when first mentioned in the text, but except for reviewers such as me, few will read this book in sequence.

Although the photographs present an exciting, euphoric sense, the text is more mundane. The text does not exclaim the wondrous diversity of form and function; unknown aspects are treated without enthusiasm. Repeatedly as I read the text, I had an alternative image in my mind where someone like Professor Jeremy Picket-Heaps or Dr Linda Goff would say ' .. . and we simply don't know how this works!' Whereupon 20+ students would immediately begin planning how they

Book reviews 373

would solve this important and exciting problem and become famous !

The book contains remarks of disparagement and frustration concerning taxonomy. I find excitement in the new discoveries of cell and molecular biology which have added an incredible wealth of new knowledge about algae, but this information is not incorporated in the text. I found mention of electron mi­croscopy no more than 10 times and molecular biology only three times. The enormous changes in green algal systematics, for example, are never mentioned! Algal systematics is cur­rently a dynamic and fast-moving field. Lay people as well as phycologists should be aware that we are living through a remarkable phycological revolution ! The rapid discoveries of new genera, families, orders and even classes are unprece­dented ! Instead, the authors ignore these many discoveries and use a classification system that was employed by Fritsch and G.M. Smith in the 1930s and 1940s. There was a tremendous opportunity to couple these exciting micrographs with the new discoveries that are changing phycology in a fundamental manner, and I was disappointed to see this opportunity missed.

There are interesting and thought-provoking remarks about algal ecology throughout the text. Here, we see a lifetime of Professor Lund's observations come to life. The text also con­tains a number of superficial environmental statements. For example, the authors suggest a human-regulated introduction of Nassula to graze down blue-green algal blooms (p. 258). However, history has taught us that introduction of other spe­cies by humans has occasionally been catastrophic to endemic species because of unforeseen interactions. The authors them­selves make this very point later in the book (p. 309).

In summary, the book is beautifully illustrated and for this reason alone, every phycologist should buy the book. The book will be a great asset for the field of phycology because all who look at it will be impressed by the beauty of algae. For this, the authors are to be commended.

R. A. Andersen, Bigelow Laboratory for Ocean Sciences, P.O. Box 475, McKown Point, West Boothbay Harbor, Maine 04575-0475, USA.