RYDBERG: NOTES ON FABACEAE—I 181 
more like that of the true H. simplicifolius.* The following 
specimens may be cited :— 
Wvyominc: Evanston, A. Nelson 2971 (flower); Carter, M. 
E. Jones (fruit). 
B. TENELLI 
7, HOMALOBUS TENELLUS (Pursh) Britton. The description 
of Astragalus tenellus Pursh, dating from 1814, was drawn 
(according to Pursh himself) from flowering specimens of the 
present species and the fruit of some other Astragalus, both of 
which had been collected by Lewis. When Pursh found that 
his description had been based on a mixture, he redescribed the 
flowering specimens, associating them with a fruiting plant 
collected by Bradbury on the Upper Missouri and giving the 
species the new name Ervum multiflorum, on account of its 
Ervum-like pods. A fragment of Bradbury’s plant in the Torrey 
Herbarium is clearly identical with the flowering specimens 
collected by Lewis: hence there is no doubt that Astragalus 
tenellus (so far as the flowering specimens are concerned) and 
Ervum multiflorum are the same. 
8. HoMALOBUS DISPAR Nutt. Nuttall first described this 
species in 1818 under the name Orobus dispar, from specimens 
that he collected at Fort Mandan. To those who consider H. 
dispar and H. tenellus identical, this note will be of no interest. 
It is here presented, however, for the benefit of those who are 
willing to admit their distinctness as species or varieties. Since 
Nuttall and Bradbury were members of the same expedition 
and often collected together, one might perhaps assume that 
Orobus dispar and Ervum multiflorum were the same. They are 
not. Nuttall’s specimen in the Torrey Herbarium agrees with 
his description in having broader leaflets than H. tenellus and 
broader short-stipitate pods. Of Phaca nigrescens Hook., 
which was described in 1830 from specimens collected by 
Richardson, there is likewise a duplicate in the Torrey Herbar- 
ium. This belongs to H. dispar, while a specimen collected by 
Nuttall on the Platte River, which was named Homalobus 
nigrescens by him and Astragalus multiflorus ty Hooker, is 
like A. tenellus Pursh. Macbride states correctly that ‘‘ Nuttall’s 
* See also Bull. Torrey Club 34: 49. 1917. 
