666 Rydberg: Astragalus and its segregates 



i6. HOMAI 



350. 



1838. 



The following are the Colorado species : //. caespitosus Nutt., 

 H. wingatanus (S. Wats.) Rydb.; H. dementis Rydb., //. tenellns 

 (Pursh) Britton, H, campcstris Nutt., H. dcciirrens Rydb,, H. 

 hylophihis Rydb., H. temnfolitis Nutt. and H, decmnbens Nutt, 

 Also : 



Homalobus grallator (S, Wats.) Rydb. 



Astragalus grallator S. Wats. Zoe 3: 52. 1892. 

 Homalobus acerbus (Sheld.) Rydb. 



Astragalus acerbus Sheld. Bull. Geol, & Nat. Hist. Surv. Minn. 



9 : 123. 1894. 

 Homalobus junciformis (A. Nelson) Rydb. 



Astragalus ptnciformis A. Nelson, Bull. Torrey Club 26 : 9. 

 1899, 



Homalobus camporum Rydb. sp. nov. 



A cespitose perennial ; stems erect, 1-2 dm. high, grayish- 

 strigose ; leaves 3-5 cm. long; leaflets 9-15, linear to nearly fili- 

 form, rarely oblong, 4-10 mm. long, 0.5-2 mm. wide, silvery- 

 canescent ; stipules ovate, somewhat scarious, strigose ; raceme 

 5-10 cm. long; flowers 7-15; bracts subulate; calyx campanu- 

 late, white-silky, about 3 mm. long ; lobes lance-subulate, about 

 y^ as long as the tube ; banner about 6 mm. long, white or ochro- 

 leucous with purple veins ; keel with a narrow purple tip ; pod 

 linear, 12-18 mm. long, 2-3 mm. wide, compressed, straight, 

 strigose. 



This is rather common on the plains and hills from Alberta to 

 Colorado and Utah and has been known as Astragalus cam- 

 pestris, A. deaimbcns and A. temiif alius Nutt. The first of these is 

 a taller plant 3-4 dm. high, more simple; its pod is 2-2.5 cm. 

 long and its keel .is broad and blunt. H. deaimbcns has an 

 arcuate pod and in H. iemiifolms the calyx-teeth are triangular 



and only )^-^ as long as the tube. As the type may be assigned : 



Wyoming: Bush Ranch, Sweetwater Co., June 10, 1900, Ave^i 

 Nelson 70^5. 



Homalobus flexuosus (Hook.) Rydb. 



PJiaca flexuosa Hook. Fl. Bor. Am, i: 141. J831. 

 Astragalus flexuosus Dougl. ; Hook. loc. cit., as a synonym. 



