Retorts

Where Have all the Diatoms Gone?

When I saw the cover of NZ Science Monthly [Nov 1994] my attention was immediately focused -- what were the organisms? I am a phycologist and algae don't often figure on covers of magazines.

However I was baffled by the caption. (1) I couldn't see any diatoms on the front cover. (I could see a filamentous alga taken with fluorescent photo-microscope.) (2) "Diatoms dominate the phytoplankton" is a difficult statement to uphold -- they do in some places and at some times but not always. (3) Diatoms were not referred to anywhere in the algal article. The only toxicity associated with diatoms is the recently discovered phenomenon of amnesic toxicity related to domoic acid production by two species of diatom. Until the late 1980s no diatoms were known to be toxic.

Dr Wendy Nelson, Collection Curator Plants, Museum of New Zealand

The cover caption was based on text supplied with the slide used, and we didn't realise there was a problem. We haven't been able to contact the photographer for comment. Thanks for the correction; it's good to see people are reading the magazine closely and it helps to keep us alert.