GENUS 26. 



PEA FAMILY. 



333 



13. Astragalus lotiflorus Hook. Low Milk Vetch. Fig. 2546. 



Astragalus lotiflorus Hook. Fl. Bor. Am. i : 152. 1833. 



Phaca loti flora T. & G. Fl. N. A. i : 349. 1838. 



Astragalus elatiocarpus Sheld. Bull. Geol. Nat. Hist. Surv. 



Minn. 9 : 20. 1894. 



Phaca elatiocarpa Rydb. Bull. Torn Club 32: 665. 1906. 

 A. nebraskensis Bates, Torreya 5: 216. 1906. 



Pubescent, with long white hairs, branched from the 

 base, nearly acaulescent, or with stems i'-3' long. Stipules 

 ovate, acuminate, ii"-2" long; leaflets 7-15, oval or oblong, 

 obtuse and sometimes mucronulate at the ape.-:, narrowed 

 at the base, 5"-8" long; flowers few, yellow, 4"-6" long, 

 in rather dense short spikes ; calyx campanulate, its teeth 

 subulate; peduncles shorter than or equalling the leaves, 

 sometimes very short ; pod i-celled, sessile, villous-pubescent, 

 ovoid-oblong, coriaceous, somewhat inflated, pointed, dehis- 

 cent, keeled along the straight dorsal suture. 



Prairies and plains. Manitoba to South Dakota, Missouri, 

 Nebraska, Texas, British Columbia and Colorado. June-July. 



14. Astragalus missouriensis Nutt. 

 Missouri Milk Vetch. Fig. 2547. 



Astragalus melanocarpus Nutt. Eraser's Cat. Name 

 only. 1813. 



Astragalus missouriensis Nutt. Gen. 2: 99. 1818. 



Densely silky-canescent all over, tufted, 

 branching from the base, 2'-$' long. Stipules 

 ovate-lanceolate, acute, 2"-4" long, leaflets 

 7-21, elliptic or obovate, obtuse but sometimes 

 mucronate at the apex, narrowed or rounded 

 at the base, 3"-$" long; flowers few, violet- 

 purple, s"-9" long in loose heads or short 

 spikes; pod i-celled, sessile, acute, oblong, 

 pubescent, dehiscent, coriaceous, circular in 

 section, slightly keeled along the ventral su- 

 ture, transversely wrinkled, about i' long. 



Plains, Kansas and Nebraska to Saskatchewan 

 and New Mexico. May-July. 



15. Astragalus Shortianus Nutt. Short's 

 Milk Vetch. Fig. 2548. 



Astragalus Shortianus Nutt.; T. & G. Fl. N. A. 1 : 331. 

 1838. 



Silvery canescent, nearly acaulescent, somewhat 

 branched from the base. Stipules ovate, acutish, 

 about 2" long; leaflets 9-15, elliptic or obovate, 

 acutish at the apex, narrowed or rounded at the 

 base, 5"-9" long; flowers blue or violet, 7"-g" long; 

 peduncles commonly shorter than the leaves; pod 

 i-celled, sessile, coriaceous, 8-shaped in section, de- 

 hiscent at maturity, lanceolate-ovoid, puberulent, 

 transversely wrinkled, strongly curved and beaked 

 at the summit, i'-ii' long. 



Plains and hills, North Dakota to Montana. Nebraska, 

 Colorado, New Mexico and Arizona. May-July. 



