PAPILIONACEAE. 553 



4-6 mm. long; leaflets 11-21, narrowly linear, distant, obtuse; flowers purple, 

 6-8 mm. long, in narrow elongated racemes; pods sessile, pendent, straight, 

 ellipsoid, appressed-pubescent with white hairs, especially on the ventral side, 

 transversely veined, 4-6 mm. long. Prairies, Minn, to S. Dak., Mo., Colo, and 

 Wyo. May-June. 



17. Astragalus microlobus A. Gray. NOTCHED-LEAVED MILK VETCH. 

 (I. F. f. 2141.) Finely canescent, about 3 dm. high. Stipules ovate-lanceolate, 

 acute, 3-4 mm. long; leaflets 7-17, linear or linear-oblong, truncate or emarginate, 

 narrowed at the base, 9-15 mm. long; flowers in loose spikes; peduncles often 

 longer than the leaves; pod sessile, ovoid or ellipsoid, reflexed, finely pubescent, 

 transversely veined, flattened on the back, keeled along the ventral suture, 4-6 mm. 

 long. Plains, Neb. to Mo. and Colo. Similar to A. gracilis. Summer. 



18. Astragalus flexudsus (Hook.) Dougl. FLEXILE MILK VETCH. (I. F. f. 

 2142.) P'inely pubescent, 3-5 dm. high. Stipules ovate or ovate-lanceolate, 

 4-6 mm. long; leaflets 9-21, linear, oblong or oblanceolate, obtuse or emarginate, 

 narrowed or cuneate at the base, 6-12 mm. long ; peduncles exceeding the leaves ; 

 flowers purplish, 9-11 mm. long ; pod sessile, cylindric, linear or linear-oblong, 

 dehiscent, pointed, 16-25 mm. long. Plains, Minn, and Neb. to Colo, and the 

 N. W. Terr. June-Aug. 



19. Astragalus distortus T. & G. BENT MILK VETCH. (I. F. f. 2143.) 

 Sparingly pubescent or glabrate, diffuse or ascending; stems 2-4 dm. long. Leaf- 

 lets 11-25, obovate or oval, emarginate or rounded at the apex, narrowed at the 

 base, 4-11 mm. long; flowers in loose short spikes; pod sessile, slightly inflated, 

 linear-oblong, coriaceous, strongly curved, 2.5-4 cm. long. In dry soil, 111. to 

 Iowa, Kans., W. Va., Miss, and Tex. March July. 



20. Astragalus elegans (Hook.) Britton. PRETTY MILK VETCH. (I. F. f. 

 2144.) Glabrous or finely strigose, erector ascending, 2.5-5 dm. high. Stipules 

 ovate, acute, about 4 mm. long; flowers 6-8 mm. long, in elongated racemes; 

 leaflets 9 17, oblong or linear-oblong, 16-20 mm. long; pod ellipsoid, pendent, 

 slightly inflated, obtuse at each end, apiculate, black-pubescent all over, 5-8 mm. 

 long. Quebec, Lab., the Saskatch. region and in the higher and northern Rocky 

 Mts. June-Aug. 



21. Astragalus Bodini Sheldon. BODIN'S MILK VETCH. Finely strigose ; 

 stems 3-10 dm. long. Stipules ovate, acute; flowers 8 lomm. long in dense racemes; 

 calyx sparingly black-strigose; leaflets 11-15, ova l? 8-15 mm. long, acute at both 

 ends; pod ellipsoid, somewhat flattened on the dorsal side, finely black-strigose, 

 obtuse, 7-10 mm. long. River valleys, from W. Neb. to Wyo. and Colo. June- 

 Aug. 



22. Astragalus Robbinsii (Oakes) A. Gray. ROBBINS' MILK VETCH. (I. F. 

 f. 2146.) Glabrous or nearly so, erect, slender, 2.5-4.5 dm. high. Stipules ovate- 

 oblong, membranous, 4-6 mm. long; leaflets 9-25, oblong, obtuse or slightly 

 emarginate. 9-17 mm. long; flowers 6-1 1 mm. long in loose racemes; pod much 

 flattened, oblong, short-stipitate, rather abruptly pointed at each end, membranous, 

 finely blackish-pubescent, dehiscent, nearly straight, 18-25 mm. long. In rocky 

 places, Vt. and N. H. June-July. 



23. Astragalus alpinus L. ALPINE MILK VETCH. (I. F. f. 2147.) As- 

 cending or decumbent, 1.5-4 dm. high, slightly pubescent, or glabrous. Stipules 

 ovate, foliaceous. 4-6 mm. long; leaflets 13-25, oval or elliptic, obtuse or retuse, 

 6-12 mm. long; flowers violet, the keel commonly darker, in short racemes; pe- 

 duncles mostly exceeding the leaves; pod membranous, stipitate, pendent, dehis- 

 cent, rather densely black-pubescent, oblong, acute, somewhat inflated, about 13 

 mm. long; calyx dark-pubescent. On rocks, N. N. Eng. to Newf. and Lab., west 

 to Alaska and Br. Col., south in the Rocky Mts. to Colo. Also in northern Europe 

 and Asia. June. 



24. PHACA L. 



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, numerous other species 

 occur in the western parts of N. Am. 



