The Dogbane* of the District of Columbia. 81 



indebted to Mr. Chas. Bullard, of Cambridge, Mass., both represent 

 broad-leaved plants of the cannabinum type. R. Brown's description* 

 refers merely to a lanceolate-leaved, glabrous plant. It contains no refer 

 ence to any of the peculiar characters of Apocynum album. The same is 

 true of the accounts given by Torrey and Hooker. It seems obvious, 

 therefore, that unless better evidence can be brought forward than that 

 furnished by the original description, the name glaberrimum is too vaguely 

 defined to supplant the well-established name album. At most it can 

 perhaps be used for one of the numerous forms of Apocynum cannabinum. 



Hypericifolium. Apocynum hypericifolium Aiton, Hortus Kewensis, I> 

 p. 304, 1798, is a clasping-leaved green-flowered plant that has not yet 

 been detected in the neighborhood of the District of Columbia. Although 

 recorded from Virginia t the species is now known from the region west 

 of the Alleghenies only. 



Incanum. [Apocynum androstemifolium \ j3. incanum De Candolle, Prodr. 

 Syst. Nat. Regn. Veg., pt. VIII, p. 439, 1844, is merely an unusually 

 pubescent individual of Apocynum androsxmifolium. Such plants not in 

 frequently occur, but they do not represent a definite form. 



Medium. Apocynum medium Greene, Pittonia, III, p. 229, December, 

 1897, is a small-flowered member of the androsxmifolium group. It was 

 first recorded by Eiolm as Apocynum androsxmifolium. 



Pubescens. A[pocynum\ pubescens R. Brown, Mem. Wern. Nat. Hist. 

 Soc., I, (1808-10), p. 68, 1811,+ from Virginia, is a pubescent form of 

 A. cannabinum, probably worthy of recognition byname. A plant agree 

 ing closely with the original description is not uncommon in the District 

 of Columbia; and the U. S. National Herbarium contains a specimen 

 collected in Virginia. This is a whitish-flowered species probably dis 

 tinct from the A. pubescens of Britton and Brown. $ 



*"A. cannabinum, foliis lanceolatis utrinque acutis, glabris, cymis 

 paniculatis, calyce tubum corolke aequante." This copy I owe to Mr. 

 Chas. Bullard. 



tDe Candolle, Prodr. Syst. Nat. Regn. Veg., pt. VIII, p. 440, 1844. 



+ Professor N. L. Britton has kindly sent me a copy of the original de 

 scription of Apocynum pubescens. It is as follows : ".-1. pubescens, foliis 

 ovato-oblongis mucronatis ; basi obtusis ; utrinque cymaque breviore 

 pubescentibns, calyce corollam sub^equante. 



" Hab. In Virginia, Mitchell, in Herb. Banks, [ubi V. S.]." 



\ 111. Flora N. United States, Canada, and Brit. Poss., Ill, p. 3. 1898. 



