The herbarium of the Academy of Natural Sciences of Drexel University houses the Academy's collection of botanical specimens. Because the Academy was one of the first scientific institutions in the New World, the herbarium holds some of the oldest and most important plant collections in the Americas. PH (the official, internationally recognized abbreviation for the herbarium at the Academy of Natural Sciences) has about 1.4 million dried, pressed specimens and plays a vital role as a resource for research on plants and on the history of American botany.

Online Databases

Data and images of all type and many historical specimens are available from JSTOR Global Plants. Be sure to search there first.

All North American lichen and bryophyte specimens from the general collections have been databased and are available from the Consortium of North American Lichen Herbaria, the Consortium of North American Bryophyte Herbaria, and the iDigBio portal.

All specimens from Taiwan are available at Plants of Taiwan.

A subset of vascular plant specimens from Pennsylvania from the general collection are available through the SEINET portal.

You can also check the herbarium’s collections database which contains a subset of specimens from the type and general collections.

Collectors and Collections

The list of collectors whose specimens are housed at PH is a veritable Who's Who of early botany and scientific exploration in North America. The table below provides just a glimpse of the highlights of our special collections; for a more complete presentation consult Mears (1981). Notably, PH has all but a few of the specimens that were brought back from the expedition of Meriwether Lewis and William Clark. (You can also check out the plants collected by Lewis and Clark in an online exhibit at or at the Lewis & Clark as Naturalists online exhibit at the Smithsonian.) B. S. Barton and G.H.E. Muhlenberg were early members of the American Philosophical Society (APS), the first scientific association in the New World, founded by Benjamin Franklin, John Bartram, and others. The APS herbarium came to PH at the end of the 19th century; other institutional and private donations have extended the scope and strength of the collection. (See APS Collections on Deposit at ANSP  APS Collections on Deposit at the Academy.)

Examples of historically significant collectors
and sources of specimens housed at PH
Collector/Source Active Period Specimens notes
Benjamin Smith Barton 18th century 2,000 Many holotypes of Pursh, Torrey & Gray, Nuttall
Frederick Pursh 18th century 1,200 North America, West Indies
Henry Muhlenberg late 18th-early 19th century l7,000 Early Eastern US
Thomas Nuttall Early 19th century 4,000 Western North America
C. W. Short 19th century 15,000 Worldwide exchange
Lewis D. von Schweinitz Early 19th century 23,000 Worldwide, plants and fungi

The herbarium also has notable strengths that reflect the taxonomic or geographic interests of past curators and associates including F. W. Pennell (Scrophulariaceae, the snapdragon family; Asia and S. America,), E. T. Wherry (Polemoniaceae, the phlox family), T. C. Porter, M. G. Henry (Pacific Northwest), B. H. Long (Eastern US), B. Stone (Pandanaceae, the screw pine family; Rutaceae, the citrus family; S. E. Asia), and A.E. Schuyler (Cyperaceae; the sedge family). PH is the primary repository and source of information for these botanists' collections. Download a pdf on these and other collectors represented in the PH.

You can view the PH collection of the Pandanaceae at:, and the PH collection of specimens collected by Forster and Forster at

The significance of the collection is further evidenced by the large Type Collection (>40,000 specimens).

Size of PH Collections
Taxon/Category Collection Size Related Documents
Vascular Plants:
  Angiosperms 1,144,800  
  Gymnosperms 6,000  
  Pteridophytes 38,000 Ferns at PH
  Bryophytes 77,990  
  Cones, Fruits and seeds 2,000 Seed Vials at PH
  Algae (including cyanophytes) 28,100 Algae at PH
  Fungi 28,600 Fungi at PH
  Lichens 24,500  
Fossil Plants 4,850  
Subtotal, General Collection 1,354,840  

See Vascular Herbarium and Cryptogamic Herbaria for more information on the collections. See Collection Policies for information on access, specimen acquisition, loans, destructive sampling and deposition of specimens. A bibliography of bibliography of recent publications on the PH Collections is also available.

The Botany Department has recently upgraded its Type and Special Collections facilities and its Herbarium cabinets. The department is currently working on Virtual Types, which will make the Type Collection available online. See Curation Upgrades.