A history is given of the parasite collection at the Beltsville Parasitological Laboratory with the names which it has been called and kinds of parasites on deposit. It is proposed that the collection henceforth be called the National Parasite Collection and for clarity and working purposes that the two main collections of which it is largely composed be called the U. S. Department of Agriculture Parasite Collection (formerly the Bureau of Animal Industry Collection) and the U. S. National Museum Helminthological Collection. Also discussed are the procedure for the deposit of policy regarding the loan of and suggestions for the packaging of specimens. In 1892, Dr. Albert Hassall (Price and Dikmans, 1943), an English-educated veterinarian and student of T. S. Cobbold, while an employee of the U. S. Department of Agriculture (USDA), started an animal parasite collection and an index to the world's literature on animal parasitology. Both of these working tools have been continuously maintained, since their inception by the USDA, under two successive agencies: Bureau of Animal Industry (BAI), 1892-1954, and Animal Disease and Parasite Research Division of the Agricultural Research Service, 1954-present. The index was named the Index-Catalogue of Medical and Veterinary Zoology and is now known internationally. Both it and the parasite collection, initially called the BAI Collection, are currently housed in Building 120, Taxonomy Building, at the Beltsville Parasitological Laboratory. Dr. Hassall established such simple and efficient procedures for recording parasite accessions and for the indexing of literature that they are still largely used today. These records enable investigators to quickly find essential information on the parasites in the collection, and the Index-Catalogue serves the same purpose with respect to the world literature on parasites (Hass, 1961). The parasite collection is now composed of several collections and has been referred to by various names during its 76-year history. These names have led to confusion as well as misunderstandings regarding the kinds of parasites on deposit and the geographic location of the collection. A history of the collection Received for publication 2 August 1968. and the names that have been applied to it, with information concerning the deposit of loan of material, and suggested procedures for the packing of specimens for mailing, is given herein in the hope that this information will be helpful to all concerned. History and names of the collection: The history of the collection is muddled because of ambiguous statements in old reports which make it difficult to understand exactly what transpired between agencies and individuals concerning specimens. Precisely what was meant by such seemingly simple terms as deposited, entered, added, catalogued, transferred, received, specimens, etc. is not always possible to determine and this creates much confusion. The first parasitologist employed by the BAI was Cooper Curtice, who was joined by an assistant, Albert Hassall, in March 1891. Curtice resigned in May 1891, and was replaced by C. W. Stiles in June. Hassall was also his assistant. Hassall was an avid collector and literature searcher, and he is credited with establishing the roots of our present parasite collection shortly after his employment, with specimens he collected and those referred to the Zoological Division of the BAI. According to Goode (1897, pp. 67-69), Stiles wrote the following letter to the Smithsonian Institution on 9 January 1894, concerning the establishment of a collection in the U. S. National