The Steere Bryophyte Herbarium holds perhaps the most important collection of bryophytes in the world in terms of the number of specimens, and the geographical and taxonomic depth and breadth. The herbarium contains approximately 640,000 specimens (520,000 mosses and 120,000 hepatics and hornworts). Of this total, approximately 24,500 (4%) are type specimens. This is the largest bryophyte herbarium in the Western Hemisphere and is among the five largest worldwide. The collection continues to grow actively today through staff collections and exchange. The emphasis is on collections from the Western Hemisphere, but virtually all areas of the world are represented.