286 LEGUMINOSAE (PEA FAMILY) 



beneath, thinner, linear-lanceolate: pod lanceolate, subfalcate; the stipe 2-3 

 times longer than the calyx. Same range as the last. 



21. Astragalus Macounii Rydb. Mem. N. Y. Bot. Gard. 1: 243. 1900. 

 Finely puberulent, rather slender, 3-5 dm. high: stipules free, ovate-lanceolate; 

 leaflets thin^ 9-17, oblong or oval, obtuse, 15-25 mm. long: peduncle surpas- 

 sing the leaves; raceme 4-10 cm. long: calyx black-hairy, its linear-subulate 

 lobes very short: corolla ochroleucous, tinged with purple: pod membranous, 

 black-hairy, acute at both ends, neither suture sulcate but the dorsal with a 

 narrow inflexed edge. A. Robbinsii occidentalis. Colorado to Montana. 



22. Astragalus elegans (Hook.) Sheld. Bull. Geol. & Nat. Hist. Surv. 

 Minn. 9: 154. 1894. Subcinereous-puberulent : stems 3-5 dm. high, slender 

 and somewhat branched: leaflets 9-17, oval, oblong, or narrower; stipules 

 ovate, acute: flowers purple, 5-7 mm. long, in long spike-like secund racemes: 

 pod sessile, ellipsoid, 1-celled, pendent, slightly inflated, obtuse but apiculate, 

 4-6 mm. long, black-pubescent. A. oroboides americana. (A. Shearis Rydb. 

 Bull. Torr. Bot. Club 31: 562. 1904.) Frequent near mountain streams; from 

 Wyoming into British America. 



23. Astragalus Brandegei Porter, Fl. Colo. 24. 1874. Canescent with 

 appressed hairs: stems several from a woody base, assurgent, 1-2 dm. high: 

 leaflets about 11, the pairs distant, linear, obtuse, involute, glabrous above, 

 10-15 mm. long: peduncles much longer than the leaves; flowers small, in a 

 loose raceme: calyx turbinate, hairy; the subulate teeth longer than the tube: 

 corolla white or yellowish, tinged with purple; the standard reflexed: pod 

 turgid, obovoid, with a shallow dorsal sulcus, short-stipitate and abruptly 

 short-pointed, 8-14 mm. long, hairy. Colorado. 



24. Astragalus asclepiadoides Jones, Zoe 2: 238. 1891. Glabrous and 

 glaucous throughout: stems single or several from the woody root, 3-5 dm. 

 high: leaves simple, sessile, ovate-orbicular, cordate, often retuse, thick, 

 3-5 cm. long: racemes (spikes) axillary, 6-8-flowered: calyx cylindric, with 

 some scattered black hairs: corolla ochroleucous; the keel purple-tipped: 

 pod 1-celled, coriaceous, oblong-ovate, acute, stipitate. Sandbars; Utah to 

 western Colorado. 



25. Astragalus Pattersonii Gray, Brand. Fl. S. W. Colo. 285. 1876. Gla- 

 brous or sparsely appressed-puberulent : stems stout, several from the crown, 

 nearly erect, often branched: leaflets oblong or cuneate-linear, obtuse or re- 

 tuse: racemes mostly elongated, loose: calyx narrowly campanulate, its lin- 

 ear recurved lobes shorter than the tube: corolla white, the keel sometimes 

 purplish-tipped: pod glabrous, elliptic-oblong, abruptly acute at apex and 

 contracted within the calyx, becoming somewhat stipe-like. Southwestern 

 Colorado and Utah. 



26. Astragalus missouriensis Nutt. Gen. 2: 99. 1818. Short-caulescent, 

 hoary with a closely appressed silky-pubescence: leaflets 5-15, oblong, ellip- 

 tic or obovate: flowers few, capitate or spicate, 10-16 mm. long, violet: 

 calyx oblong, the teeth very slender: pod oblong, 2.5 cm. long, acute, ob- 

 tuse at base, pubescent, nearly straight, obcompressed or obcompressed- 

 triangular, depressed on the back and the ventral suture more or less promi- 

 nent, transversely rugulose. Throughout our range, east on the plains and 

 south to Texas. 



27. Astragalus Shortianus Nutt. in T. & G. Fl. N. Am. 1: 331. 1838. 

 Usually subacaulescent, silky-canescent with a very closely appressed pu- 

 bescence: leaflets obovate or ovate, 12-18 mm. long: peduncles scape-like, 

 commonly shorter than the leaves: calyx 12 mm. long, cylindric, teeth shorter 

 than the tube: corolla violet or blue, rather large and showy: pod 3-5 cm. 

 long, ovate or ovate-lanceolate, thick, coriaceous, obcompressed, dorsal suture 

 intruded, approaching the ventral, transversely rugulose, pointed and strongly 

 arcuate, more or less pubescent. (A. cyaneus Gray, PI. Fendl. 34. 1854.) 

 Wyoming to New Mexico. 



28. Astragalus chamaeluce Gray, Ives Rep. 10. 1861. Silvery-canescent, 

 with a dense silky-pubescence: stems numerous, short (2-5 cm.), prostrate 

 or nearly acaulescent: leaflets 5-13, from oval to oblong, 4-8 mm. long: pe- 



