The Academy of Natural Sciences of Philadelphia (ANSP) has been one of the important centers of diatom studies in the U.S. since the 19th century. In 1950's, Dr. Ruth Patrick assembled personal collections of F.W. Lewis, C. Febiger, J.A. Shulze, F.J. Keeley, and C.S. Boyer into a single Diatom Herbarium. Dr. Charles Reimer, the Curator of the Herbarium for almost 50 years, together with Dr. Patrick developed the Herbarium into a key resource for diatom research. Contributors and members of the Editorial Review Board for the Diatoms of the United States regularly participating in taxonomic workshops held at the Diatom Herbarium and use its resources to clarify various taxonomic problems and to create taxa pages.

The goal of the project supported by the National Science Foundation was to make the resources of ANSP Diatom Herbarium easily accessible to scientists. The current Herbarium staff members created a new online database, which includes a gallery of images of type specimens. Imaging of type specimens led to re-evaluation of several taxa, the results of which were published in the scientific literature and contributed to this online flora. The reorganization of the Herbarium that includes re-housing of the materials, entering data into database, and georeferencing is on-going.


  • National Science Foundation

    - Marina Potapova


Marina Potapova

Content Editor, Monoraphid Diatoms Diatoms of North America, Editoral Review Board

Curator Diatom Herbarium, Academy of Natural Sciences of Philadelphia, Drexel University

Jen Beals

Ph.D. Student University of Arkansas

Jonathan English

Research Assistant Diatom Herbarium, Academy of Natural Sciences Philadelphia

Ian O'Malley

Undergraduate Student, Coop Program Drexel University

Alys Kirsch

Curatorial Assistant

The ANSP Diatom Herbarium was originally cataloged on cards by taxon and location.
Ruth Patrick in the field.
C W Reimer 1974
Charlie Reimer, at the ANSP Diatom Herbarium.
Ruth Patrick
Ruth Patrick was awarded the National Medal of Science in 1996, from President Bill Clinton.
Reimer Pilotknob
Image Credit: Mark Edlund
Charlie Reimer, at Pilot Knob, Iowa. Dr. Reimer taught the field course in Iowa from 1966 to 1989.