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 crasskarpus 

 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. sulphiirescens. 

 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 Terr. 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 Cation; 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- 



