Genus 26. 



PEA FAMILY. 



Flexile 



19. Astragalus flexuosus (Hook.j Dou 

 Milk Vetch. Fig. 2552. 



140. 1830. Not Astragalus 



Phaca elongata Hook. Fl. Bor. Am. i : i 



elongatus Willd. 1803. 

 Phaca flexuosa Hook. Fl. Bor. Am. i : 141. 1830. 

 Astragalus flexuosus Dougl. ; Hook. Fl. Bor. Am. 



I : 140. 1830. 



Erect or ascending, finely pubescent, branching froin the 

 base, i°-ii° high. Stipules ovate or ovate-lanceolate, 2"-3" 

 long; leaflets 9-21, linear, oblong or oblanceolate, obtuse or 

 emarginate at the apex, narrowed or cuneate at the base, 3"-6" 

 long ; peduncles exceeding the leaves ; flowers purple or pur- 

 plish, 4"-5" long; pod i-celled, sessile, cylindric, linear or 

 hnear-oblong, puberulent, dehiscent, pointed, 8"-i2" long. 



Prairies and plains, Minnesota to Kansas, Saskatchewan, Al- 

 berta and Colorado. June-Aug. 



27. PHACA L. Sp. PL 755. 1753. 

 Perennial herbs, similar to Astragalus, mostly with pinnate 

 leaves, and racemed or spicate, purplish or purple flowers. Pod 

 much inflated, membranous in texture, strictly i-celled, neither 

 of the sutures intruded. [Greek, Lentils.] 



A large genus, mainly of the north temperate zone. Besides the following, 

 species occur in the western parts of North America. Type species : Phaca baetica 

 Leaflets 7-21, oblong, elliptic or ovate. 



Pod stalked ; flowers slender-pedicelled. 

 Pod sessile ; flowers short-pedicelled. 

 Leaflets only i, or sometimes 3-5, very narrowly linear. 



num 

 L. 



1. P. 



2. P. 



3. P- 



erous other 



americana, 



neglecta. 



longifoha. 



I. Phaca americana (Hook.) Rydb. Arctic Milk 

 Vetch. Fig. 2553. 



P. frigida var. americana Hook. Fl. Bor. Am. I : 140. 1830. 

 Astragalus frigidus var, americanus S. Wats. Bibl. Index, i : 



193. 1878. 

 Phaca americana Rydb.; Britt. & Brown, 111. Fl. 2: 304. 1897. 



Erect, nearly simple, glabrous, i°-2° high. Stipules folia- 

 ceous, ovate-oblong, 2"-6" long; leaflets 7-17, oval or ovate- 

 lanceolate, 9"-iS" long ; peduncles generally exceeding the 

 leaves ; flowers white, 8"-9" long, in loose racemes ; pedi- 

 cels filiform, 4' long in fruit ; pod i-celled, stipitate, in- 

 flated, membranous, io"-i2" long, acute at each end, ob- 

 long, dehiscent at maturity, glabrous, shining. 



In wet rocky places, Quebec to British Columbia and Alaska, 

 south to South Dakota and in the Rocky Mountains to Wyo- 

 ming. June-July. 



2. Phaca neglecta T. & G. Cooper's Milk Vetch. 

 Fig- 2554. 



Phaca neglecta T. & G. Fl. N. A. i : 344. 1838. 

 Astragalus Cooperi A. Gray, Man. Ed. 2, 98. 1856. 

 Astragalus neglectus Sheldon, Bull. Geol. Surv. Minn. 9 ; 59. 

 1894. 



Glabrous or nearly so, erect, l°-2° high. Stipules ovate, 

 acute, l"-2" long; leaflets 9-21, thin, oblong or elliptic, 

 often minutely pubescent beneath, 8"-i2" long, obtuse or 

 emarginate at the apex, narrowed at the base; peduncles 

 shorter than or equalling the leaves ; flowers white, S"-7" 

 long, in rather loose spikes ; calyx pubescent with blackish 

 hairs, its teeth subulate; pod i-celled, sessile, the ventral 

 suture somewhat intruded, inflated, coriaceous, ovoid, acute, 

 glabrous, slightly furrowed along both sutures, 6"-io" long, 

 S"-6" thick. 



On banks and shores, Quebec to Niagara, west to Minnesota 

 and Iowa. June-July. 



25 



