does not have a key to their genera! Thus to tackle them you need to fork out £40.25 and
purchase Blue-Green Algae of the British Isles: An Interactive Key. Version 2.1 B.A
Whitton CD-ROM with license number and manual. University of Durham. 2003.
Be aware however, that Cyanobacterial taxonomy is in a similar primitive state to that of
the lower fungi. With little to go on morphologically, and great variation in dimensions
with environment, the chances of identify ing anything below generic level is slim, and
the whole group need to be typified using genomics before species can be defined at all
meaningfully. The same applies to many of the other true (eukaryotic) algal groups, but
as far as our collective knowledge goes they are pretty well dealt with in the rest of the
book, with keys to the orders, genera and species. All that is, except the diatoms. The
Freshwater Algal Flora 2002 ean be used in conjunction with A Coded List of
Freshwater Algae of the British Isles, 2003 - now in its second edition as an Excel
spread sheet listing all current names with their synonyms and authorities, down-loadable
from the CEH website at http://www.ceh.ac.uk/data/algae/algae_index.html. (unless
you want to buy a spiral bound copy for £106). When I analyzed the 1988 edition of the
checklist there were around 3910 species of algae including 1655 species of diatoms on
the list. Freshwater Diatoms with some 108 or so genera, are covered in two recent
databases. The ADIAC diatom image database, a collaboration between The Royal
Botanic Garden, Edinburgh and the University of Newcastle upon Tyne aims to provide
photomicrographs of all the diatom taxa. http://rbg-web2.rbge.org.uk/ADIAC/db/
adiacdb.htm. A less ambitious guide is the Common Freshwater Diatoms of Britain
and Ireland multi-access key CD Rom developed for the environment agency and
detailed at: http://craticula.ncl.ac.uk/EA DiatomKey/ html/index.html.
Of the less comprehensive guides to Freshwater Algal identification, there is a wide
selection for beginners. The spiral bound How to Know the Freshwater Algae. GW.
Prescott.William C Brown. Edition 3. 1978 is still available and keys out all the genera
with illustrated examples. Less ambitious arc: A Beginner's Guide to Freshwater Algae
by our own recorder for algae Hilary Belcher together with Erica Swale, NERC. 1976.
in which they tackle examples from 110 algal genera; and An Illustrated Guide to
River Phytoplankton. 1979, by the same authors dealing with 109 example taxa; both
fully illustrated with line drawings. Introduction to Freshwater Algae by Allan Pentecost
1984. Richmond, similarly covers around 500 taxa. For the serious beginner there can
be no better introduction than Freshwater Algae, their microscopic world explored
by Hilda Canter-Lund and John Lund. 1996. Biopress. A magnificent large format book
with superb colour micrographs of a wide range of genera and an authoritative narrative
text. To get into the detailed taxonomy, ultrastrueture, molecular biology and ecology of
all the algal groups Phycology. 4th edition by Robert Lee. CUP. is a must. The big snag
with algae of course is that you need a high power light microscope, ideally with phase-
contrast, to have a hope of identifying them. And many of the smaller unicells cannot be
tackled without a scanning-beam electron microscope to observe ultramicroscopic hairs/
scales on their flagella or cell surfaces! No doubt one day kits will be available to extract
the DNA from filtered samples and identify them routinely. Then perhaps algology will
Essex Field Club Newsletter No. 59, May 2009
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