VOL. XIII, PP. 79-90 September 28, 1899 



PROCEEDINGS 



OK THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



THE DOGBANES OF THE DISTRICT OF COLUMBIA * 

 BY GERRIT S. MILLER, Jr. 



Two dogbanes, Apocymim cannab'mum and A.androsssmifoliKm, 

 were recorded in the first detailed list of plants of the District of 

 Columbia, published nearly seventy years ago.f In 1876 the 

 same plants were included in the ' Flora Columbiana ' of the Po- 

 tomac-Side Naturalists' Club, Avithout special comment.^ Five 

 years later Ward relegated the second species to the list of plants 

 whose occurrence in the vicinity of Washington is doubtful. § At 

 the same time 1 1 he recognized two forms oi Apocynum cannabinum^ 

 the tj^pical A. cannnblnum canndbinum, of general distribution, 

 and A. cannabinnmglabcrrimvm, found only on the fiats of the Po- 

 tomac River bottom at Little Falls. In 18S6 Knowlton discovered 

 a species which he recorded as Apocynum (mdrosfeinifoUuin,^^ and 

 in 1892 ^^i' and 1896 ft Holm published further records of a plant 

 that he supposed to be the same. In 1897 Greene raised the 

 Apon/iiwn caiimibiu am glnherrimnvi of Ward to specific rank under 

 the name A. album, and at the same time described Holm's A. 



* Published by permission of the Secretary of the Smithsonian Insti- 

 tution. 



t Flor;« Ooluml)ian8e Prodromus, p. 24, 1830. 

 t Flora Cohiiiibiana, p. 16, 1870. 



I Guide to the Flora of Washington and Viciuitv (Bull. U. S. Nat. Mus. 

 No. 22), p. 12, 1881. 



II Ibid., p. 97. 



T[ Proc. Biol. Soc, Washington, III, p. 108. 

 *^Mbid., VII, p. 118. 

 ttlbid., X, p. 36. 



20—15101,.- Siir. Wash., Vol. XTII, 1800 (VO) 



