Notes on the diatom collection of the Natural History Museum, London (BM) VIII: the types of Arachnoidiscus in Brown’s monograph (Brown 1933)

Abstract

Nicholas Edward Brown, a botanist primarily interested in the African flowering plant flora, was also an active member of the Quekett Microscopical Club. In 1933, he published a monograph on the genus Arachnoidiscus. Brown had described Arachnoidiscus antarcticus in 1920 and went on to add a further 19 more new species to the genus. The present contribution is not intended as a review of Brown’s species in Arachnoidiscus, but an account of the specimens available in BM that went towards its creation, with some notes on nomenclature. A few words are devoted to other species Brown described, and other names he proposed.

Keywords:

• Nicholas Edward Brown
• type specimens
• Arachnoidiscus
• specimen collections

Conclusions

There are few conclusions to be made beyond pointing out, once again, that this is not a review of the genus Arachnoidiscus, but a review of the specimens available in BM attributed to Nicholas Edward Brown that formed the basis of his monograph (Brown 1933a) and could form the basis of any new monographic work undertaken. In addition, there are a few comments on some of Brown’s other species, largely to indicate that while Brown provided numerous decent observations, many of these names require re-examination.

But there are two general conclusions worth commenting on. First, it is noteworthy that Brown relied heavily on the Atlas der Diatomaceen-kunde, a large atlas of specimen images colloquially known as Schmidt’s Atlas, a compendium put together over a lengthy period of time (1874–1959) that involved numerous authors (see TL-2, p. 243, item no. 10.871). Brown was working nearly a century ago, but to create a comprehensive atlas today would be considerably easier to compile utilizing current computing capabilities. And, of course, it would have the advantages of being online only, open-ended and open access, linked to existing databases of names (e.g., DiatomBase Kociolek et al. 2023), linked to nomenclatural registration systems (Phycobank, https://www.phycobank.org/) and, more importantly, would be (should be!) community driven.

Second, and with respect to the notion of ‘community driven’ projects, knowledge of past diatomists and their collections (as well as mounters and microscopists) is primarily captured by the efforts of a community of amateur diatomists and microscopists that work, more or less, on their own outside mainstream scientific outlets. For example, the magnificently informative ‘Historical Makers of Microscopes and Microscope Slides’ (http://microscopist.net/) (Stevenson 2023) and ‘A Cabinet of Curiosities’ (http://www.victorianmicroscopeslides.com/slides.htm) (Lynk 2023) helped enormously in tracking down lost people, collections and slides for this, and similar studies.

Both of these general points could springboard a new era of online ‘Atlases’ designed to help everyone steer around the known diatom diversity and those who have studied and brought it to our attention.

Acknowledgements

The author is more than grateful to Estrela Figueiredo (Nelson Mandela University, Gqeberha [Port Elizabeth], South Africa) for answering my questions about Nicholas Edward Brown and encouraging me to look into Brown’s diatom collection and its whereabouts, and to Howard Lynk (http://www.victorianmicroscopeslides.com/aboutme.htm) for providing copies of his various articles on Charles Topping; and to a reviewer for a number of points I had overlooked. Eileen Cox and two reviewers provided numerous useful comments and suggestions.

Notes

1 The correct reference to the Ehrenberg herbarium is BHUPM.