FABACEAE. 209 



Leaflets linear or linear-oblong, acute, ascending. 

 Leaflets narrowly linear, silvery-canescent. 



Low and very cespitose, 1-2 dm. high; pods about 1.5 cm. long; keel 



with a very narrow end. 8. H. camporum. 



Tall, 3-4 dm. high, more simple; pods 2-2.5 cm. long; keel with a 



broader end. 9. H. campestris. 



Leaflets oblong or lanceolate, strigose but not canescent ; terminal leaflet 

 longer, tapering into the rachis without a distinct articulation ; racemes 

 long and lax. 10. H. decurrens. 



Leaflets, at least of the lower leaves, oval or elliptical, spreading. 



n. H. hylophilus. 

 Calyx-teeth triangular, Y*~Yz as long as the tube ; leaflets linear. 



Low, depressed; pods 12-15 nim. long, sessile. 12. H. tenuifolius. 



Taller, 2 dm. or more high; pods over 15 mm. long, often slightly stipitate. 



13. H. junciformis. 

 FLEXUOSI. 



Pod oblong, over 5 mm. in diameter. 



Inflorescence short; flowers about 15 mm. long; pod glabrous. 



14. H. Hallii. 

 Inflorescence elongated and lax; flowers about 10 mm. long; pod pubescent. 



15. H. Fendleri. 

 Pod linear, 2-3 mm. thick. 



Pod abruptly contracted into a short or obsolete stipe. 



Stem decumbent; stipe minute or obsolete. 16. H. flexuosus. 



Stem erect; stipe almost equalling the calyx. 17. H. proximus. 



Pod gradually tapering into the short stipe. 18. H. Salidae. 



MACROCARPI. 

 One species. 19. H. macrocarpus 



1. Homalobus caespitosus Nutt. (Astragalus caespitosus A. Gray.) On 

 dry hills from Ass. and Mont, to Colo, and Utah. Alt. 4000-6000 ft 

 Livermore, Larimer Co.; north of La Porte. 



2. Homalobus grallator (S. Wats.) Rydb. (A. gr dilator S. Wats.) On 

 river banks from Colo, to Nev. Steamboat Springs. 



3. Homalobus wingatanus (S. Wats.) Rydb. (A. Wingatanus S. Wats.) 

 On dry hills in S. Colo, and N. Mex. Mancos. 



4. Homalobus Clementis Rydb. In the mountains of Colo. Alt. up to 

 10,000 ft Marshall Pass; Sangre de Cristo; Big Creek Gulch. 



5. Homalobus tenellus (Pursh) Britton. (Astragalus tenellus Pursh ; As- 

 tragalus multiHorus (Pursh) A. Gray) On plains and hills from Minn., Sask. 

 and Yukon to Neb., Colo, and Nev. Alt. 4000-10,000 ft. Near Empire; 

 Ward, Boulder Co.; Swallows, between Canon City and Pueblo; Estes 

 Park; near mouth of Leroux Creek; Middle Park; Ft Collins; near Boul- 

 der; mountains between Sunshine and Ward; Marshall Pass. 



6. Homalobus acerbus (Sheld.) Rydb. (A. acerbus Sheld.) In the 

 mountains of Colo. Alt. about 8000 ft. Glenwood Springs. 



7. Homalobus decumbens Nutt. (A. decumbcns A. Gray) In the moun- 

 tains of Colo, and Wyo. Steamboat Springs. 



8. Homalobus camporum Rydb. On plains and hills from Alb. to Colo, 

 and Utah. Alt. 8000-10,000 ft Grayback mining camps and Placer Gulch; 

 North Park. 



9. Homalobus campestris Nutt. (A. campestris A. Gray; A. convallarius 

 Greene) On plains from Mont, and B. C. to Colo, and Utah. Alt. up to 



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