About the Diatom Collections

The core research collection was founded upon the collections of nineteenth- and early twentieth century [amateur] diatomists, and includes material from as early as 1771. Many additional collections have been contributed by diatomists working on all continents. 

Slides are catalogued both geographically and taxonomically; the geographic file is computerized. There are several other important collection resources. Unique in the world is the "New Species File" renamed to the Diatom New Taxon File, which includes in excess of 133,000 5X8 cards for both newly described taxa and previously described diatoms that have been taxonomically revised from 1933 to the present. These cards include descriptions, illustrations, locality and type information, and source references for both the current name and for the basionym taxon where applicable. The Bibliography File includes approximately 60,000 3X5 cards with references for individual articles and monographs about diatoms. The majority of these references are available in the Herbarium's extensive library and reprint collections. There are also card files cataloging the occurrence of individual taxa on herbarium slides, listing references containing SEM and TEM images of diatoms, and summarizing diatom ecological data gleaned from the literature.