History of the Diatom Herbarium

Diatom Herbarium Origins

The precise origin and early history of the Diatom Herbarium remains buried in the archival manuscript collections of the Academy of Natural Sciences and other early natural history museums awaiting the scrutiny of historical biological researchers.

Present evidence indicates that interest in diatoms and other algae may first have come to the Academy through certain enthusiasts of microscopical objects in Philadelphia who joined together in the late 1850's to form the "Microscopical Society of Philadelphia." This society joined with the biological department of the Academy of Natural Sciences in 1868, shortly after the Civil War, forming the Biological and Microscopical Section, which remained intact until sometime around the First World War. In 1925, the microscopical collections, including diatoms, came under the care of the Leidy Microscopical Club and the Microscopy Department. The earliest published work on diatoms from this historical background seems to have been the papers of F. W. Lewis who published in the Proceedings of the Academy of Natural Sciences in the early 1860's.

 Diatoms colored circle

From this time to about the close of the nineteenth century there were two principal avid diatomists who accumulated large numbers of diatom specimens and left their curated collections and a backlog of unsorted material to the Academy:Christian Febiger and John A. Schulze. Although they did not publish much in literature, they were in active correspondence with many of the top diatomists during this period of time and as a result they accumulated by exchange large numbers of original materials from the active workers in the field. Christian Febiger's (1817-1892) large collection of diatoms was given to the Academy by his heirs. Febiger was a member of the Academy and often studied there. He was an industrialist who developed, as a hobby, an avid interest in diatoms. In so doing he gathered substantial literature on the subject and exchanged correspondence with several European diatomists of the time. This correspondence lead to an exchange of specimens and brought to his collection sets of slides from the top foreign diatomists of the world (for a further accounting, see Peterson, 1942).

20th Century

From the beginning of the twentieth century to 1927 the most active worker in diatoms at the Academy was Charles S. Boyer (1856-1928), a school administrator (Reimer et al., 1991). He too was in active correspondence and exchange of materials with other diatomists and, as his two predecessors, accumulated a large collection of his own which was also added to the Academy's holdings. His most significant work was the publication of "Synopsis of the North American Diatomaceae," (1927) the first such account for North America. During his tenure at the Academy there were two other persons who were extremely interested in diatoms and who contributed in specimens, in time, and in money to the collection; these men were Dr. Thomas Stewart and Mr. Frank Keeley. T. Chalkley Palmer, a president of the Academy, also made contributions. After the death of Mr. Boyer in 1928, work on the diatoms at the Academy was principally under the care of Mr. Frank Keeley who was an avid curator of materials. The collection, for use and for publication, was relatively dormant following Boyer’s death until 1937 when Ruth Patrick became the Curator of the Leidy Microscopical Club collections.

During her first (about 15) years at the Academy, Ruth Patrick took on the tremendous job of intercalating the various individual collections and exsiccatae into a single diatom herbarium. At the same time she also acquired other collections, including a large amount of unmounted material of P. T. Cleve (from the Naturhistoriska Riksmuseet in Stockholm); the Rabenhorst exsiccatae set (from the Missouri Botanical Garden); and the Pease collection of several thousand slides from Penn State University.

Ruth Patrick

During this time she also initiated the "New Taxon File". This file was most critical for diatom investigators because of the cessation of Mills Index (Mills 1816-1932), a series of publications that attempted to list and reference all diatom names published in the world between 1816 and 1932. The file was started with the objective of covering all diatom literature references published on new and transferred taxa after 1932. She, however, embellished this objective by putting the literature references on 5x8 cards and including entries such as: nom. nov., stat. nov., Holotype, Lectotype, Neotype, Paratype, etc., none of which were specifically designated in F. W. Mills Index, as well as locality information and photocopied descriptions and images for each taxon. This file remains unique in the world of diatom research. Additionally, Ruth Patrick initiated a world literature citation file covering all obtainable references to any paper or monograph discussing or mentioning diatoms. This file is also unique and is still maintained and is also supplemented with electronic literature records.

Around the late 1950's-early '60's Ms. Margaret V. Henderson and Dr. C.W.Reimer became responsible for compilation of literature and new species data. These entries were continued and expanded in the 1980's with the hiring of library assistants.

In 1946, the Diatom Herbarium was transferred to the newly formed Department of Limnology under the curatorship of Dr. Ruth Patrick. From 1954 to 1959, Dr. M. H. Hohn became the active (Associate) Curator of the herbarium under the supervision of Dr. Patrick. From 1960 to 1974, Dr. C.W. Reimer was the active (Associate) Curator and later Curator under the continued supervision of Dr. Patrick until 1975 when Dr. Patrick became Curator Emeritus. Dr. Reimer was responsible for the addition of cleaned material and slides from Dr. N. Foged (Denmark); McCall (Scotland); Manguin (France) and others. He also established a new file, the SEM-TEM File. All illustrations found in the weekly literature search of library accessions were included, whether or not they referred to new taxa. References to all published electron microscope illustrations of diatoms were included. This file was kept current until the mid-1990’s and has records for over 5,300 diatom taxa. Dr. Reimer also arranged funding for Haydon Rochester, a private consultant, to enter all information from the Geographic Card File into a computer database.

In 1981 the herbarium was transferred from the Department of Limnology and Ecology to the Division of Systematics and Evolutionary Biology (now the Center for Systematic Biology and Evolution) as a separate department. In 1991, Dr. Reimer was officially retired from the Academy, but was encouraged to continue curation and responsibility for the herbarium. Shortly after that, Dr. Ed Theriot became curator of the Diatom Herbarium and held the position until1995. He initiated efforts to computerize herbarium records. He created a database, and with the help of Earle Spamer and Su-ing Yong, entered nearly 40,000 records from the species-occurrence card file. Dr. Reimerreassumed responsibilities as curator (Curator Proprius) in 1995 andcontinued maintaining herbarium activities until his death in 2008.

Click here to learn more about Charles Reimer

Click here to learn more about Ruth Patrick

Present Day

Dr. Marina Potapova, formerly a research scientist in the Phycology Section in the Patrick Center for Environmental Research, assumed her duties as the curator of the Diatom Herbarium in January 2008 and currently maintains herbarium operations with the assistance of Laura Aycock, the herbarium Collection Manager.


Mills, F.W. 1816-1932. An index to the genera and species of the Diatomaceae and their synonyms, 3 vol., 1726pp., with taxon names listed from A to Z.

Patrick, R.P. 1982. The history of the science of diatoms in the United States of America.Pages 11-20 In D.G. Mann. (Ed). Proceedings of the 7th International Diatom Symposium, Philadelphia, PA, 1982. Koeltz, Koenigstein.

Peterson, G. Bernard. 1942. A niche for amateurs. Frontiers: A Magazine of Natural History pp 133-135, June, 1942.

Potapova, M. 2010. The ANSP Diatom Herbarium: an important resource for diatom research. Proceedings of the Academy of Natural Sciences of Philadelphia 160: 3-12.

Reimer, C.W., M.V. Henderson and R.K. Mahoney. 1991. Contributions of Charles S. Boyer (1856-1928) to the knowledge of diatoms (Bacillariophyceae): Biographical notes, literature and taxonomic summary, with type designations. Proceedings of the Academy of Natural Sciences of Philadelphia 143: 161-172.