. II.] 



PEA FAMILY. 



307 



2. Orophaca sericea (Nutt.) Britton. Hoary Milk Vetch. (Fig. 2155.) 



Phaca sericea Nutt.; T. & G. Fl. N. A. i: 343. 1838. 



Astragalus sericoleucus A. Gray, Am. Journ. Sci- 

 (II.) 33: 410. 1862. 



Villous-pubescent, densely tufted, and spread- 

 ing on the ground from a deep root, the stems 

 3 / -4 / long. Leaves short-petioled, 3-foliolate; 

 leaflets oblong or oblanceolate, acute or obtus- 

 ish at the apex, narrowed or cuneate at the 

 base, 2 // -5 // long; peduncles slender, 2-6-flow- 

 ered, equalling or exceeding the leaves; flowers 

 bluish-purple, about 3" long; pod i-celled, ses- 

 sile, ovoid-oblong, coriaceous, acute, villous- 

 pubescent, about 3" long, partly enclosed by 

 the calyx. 



< 



In dry, sandy or rocky places, Nebraska and Col- 

 orado. May-July. 



27. SPIESIA Neck. Elem. 3: 13. 1790. 



[OXYTROPIS DC. Astrag. 19. 1802.] 



Herbs, sometimes shrubby, and mostly acaulescent, with odd-pinnate leaves, and race- 

 mose or spicate flowers. Calyx-teeth nearly equal. Petals clawed; standard erect, ovate or 

 oblong; wings oblong; keel erect, shorter than or equalling the wings, its apex mucronate, 

 acuminate or appendaged; stamens diadelphous; anthers all alike; style filiform. Pod ses- 

 sile or stipitate, 2-valved, i -celled, or more or less 2-celled by the intrusion of the ventral 

 suture. [In honor of Johann Karl Spies, a German botanist.] 



About 120 species, natives of the north temperate zone. In addition to the following, some n 

 others occur in the western and northwestern parts of North America. 



leaves simply pinnate. 



Plants i '-4' high; heads few-flowered. 



Pod membranous, pubescent, much inflated, i-celled. 

 Pod coriaceous, ovoid, little inflated, pubescent, partly 2-celled. 

 Calyx gray-pubescent; leaflets 7-9, oblong. 

 Calyx dark-pubescent; leaflets 7-21, linear. 

 Plants 6'-i8' high; heads or spike-like racemes many-flowered. 

 Sparingly pubescent; flowers 8"-g" long; pods papery. 

 Silky-pubescent; flowers ^"-15" long; pods coriaceous. 

 Leaves pinnate, the leaflets verticillate. 



Pod scarcely longer than the calyx, its tip spreading. 

 Pod 2-3 times as long as the calyx, its tip erect. 



1. 5". inflata. 



2. S. multiceps. 



3. 6'. arctica. 



4. 5". campestris. 



5. 5". Lamberti. 



6. S. splendens. 



7. 5. Belli. 



i. Spiesia inflata (Hook.) Britton. Inflated 

 Oxy trope. (Fig. 2156.) 



Oxytropis arctica \ar.inflata Hook. Fl. Bor. Am. i: 



146. 1833. 

 Oxytropis podocarpa A. Gray, Proc. Am. Acad. 6: 234. 



1864. 

 Spiesia inflala Britton, Mem. Torr. Club, 5: 201. 1894. 



Acaulescent or nearly so, more or less villous-pu- 

 bescent, much tufted, \'-\' high. Stipules mem- 

 branous, imbricated, adnate to the petiole, lanceolate, 

 about 2" long; leaves pinnate; leaflets 9-21, linear, 

 2 //_4// long, about y z " wide, obtuse or obtusish; pe- 

 duncles i-2-flowered, scarcely exceeding the leaves; 

 flowers violet, 7 // -8' / long; calyx densely dark-pu- 

 bescent; pod membranous, much inflated, i-celled, 

 ovoid, pubescent, short-stalked or sessile in the 

 calyx, about 9'' long, pointed; ventral-suture slightly 

 intruded. 



Arctic and alpine ; Labrador and arctic America, south 

 in the Rocky Mountains to Colorado. Summer. 



