FABACEAE. 203 



1. Geoprumnon succulentum (Richardson) Rydb. (Astragalus succulentus 

 Richardson; A. prunifer Rydb.) On plains and hills from Sask. and Mont, 

 to S. D. and Colo. Alt. 4000-7000 ft. Ft. Collins; foot-hills, Larimer Co.; 

 Colorado Springs; Cucharas River, below La Veta; Walsenburg; bank of 

 Cache la Poudre; Horsetooth Gulch; Velmont. 



2. Geoprumnon crassicarpum (Nutt.) Rydb. (Astragalus crassicarpus 

 Nutt. ; A. caryocarpus Ker) On prairies and plains from Man. and Mont, 

 to Mo. and Tex. Alt. 4000-5000 ft. Plains near Denver; South Park; 

 Lamar; Ft. Collins; Howe's Gulch. 



ii. ASTRAGALUS L. Loco WEED, MILK VETCH. 



Plants cespitose, subscapose, villous-pubescent ; pods sulcate on both sutures. 

 Pod glabrous, deeply sulcate. i. A. mollissimus. 



Pod villous, slightly sulcate. 



Calyx densely villous; leaflets 6-12 pairs. 2. A. Bigelovii. 



Calyx sparingly nigrescent ; leaflets 3-6 pairs. 3. A. anisus. 



Plants with elongated leafy stems. 



Pods not sulcate or slightly so on the lower suture, round or nearly so in 



cross-section. 



Bracts linear-lanceolate, long-attenuate ; the lower almost as long as the 

 calyces ; calyx-teeth all narrow, subulate, fully half as long as the tube ; 

 pod glabrous. 4. A. canadensis. 



Bracts ovate to lanceolate, scarcely half as long as the calyces ; calyx-teeth 

 short, less than half as long as the tube ; the upper broader ; pod more or 

 less hairy. 5. A. oreophilus. 



Pod deeply sulcate on the lower suture, cordate or triangular in cross-section. 

 Pod with appressed gray or black pubescence. 



Corolla purple or pink, seldom white ; calyx-teeth much shorter than the tube. 



6. A. nitidus. 

 Corolla sulphur-yellow ; calyx-teeth almost equalling the tube. 



7. A. sulphur esc ens. 

 Pod villous with long spreading hairs. 



Corolla ochroleucous ; bracts broadly spatulate, very obtuse. 



8. A. virgultatus. 

 Corolla purple ; bracts ovate-lanceolate or oblong, often acutish. 



9. A. goniatus. 



1. Astragalus mollissimus Torr. On prairies from Neb. and Wyo. to 

 Tex. and N. M. At. 4000-5000 ft. Ft. Collins; Lamar. 



2. Astragalus Bigelovii A. Gray. In dry soil from Colo, to Tex. and 

 Ariz.; also in Mex. Alt. 4000-5000 ft. Grand Junction. 



3. Astragalus anisus Jones. On dry mesas of Colo. Pueblo. 



4. Astragalus canadensis L. Among bushes and in meadows from Que. 

 and B. C. to Fla. and Calif. Alt. 4000-5000 ft. La Veta; Roswell; Lower 

 Boulder Canon, Boulder Co. ; Ft. Collins ; Poudre flats ; between Ft. Col- 

 lins and La Porte; gulch west of Soldier Canon; along Conejos River. 



5. Astragalus oreophilus Rydb. (A. Mortonii Coulter, in part; not Nutt.) 

 Among bushes in Colo. Alt. 5000-8000 ft. Pagosa Springs; mountains, 

 Larimer Co.; Wahatoya Creek; Trimble Springs, above Durango; Stove 

 Prairie, Larimer Co.; plains and foot-hills near Boulder; Walsenburg. 



6. Astragalus nitidus Dougl. (A. adsurgens Hook., .and Am. auth. ; not 

 Pall.) On hills and plains from Minn., Sask. and Alb. to Colo, and Oregon. 

 Alt. 4000-11,000 ft. South Park; Manitou Springs; Platte River; Chey- 



