458 NORTH AMERICAN FLORA [Volume 24 



7. Hesperastragalus obispensis Rydb. Bull. Torrey Club 

 53: 167. 1926. 



An annual; stem 1 dm. high, branched at the base, the branches ascending or spreading, 

 minutely strigose; leaves 2-3 cm. long, spreading; stipules herbaceous, deltoid, acuminate, 2 

 mm. long; leaflets 9-11, elliptic or oblong, mostly rounded at the apex, 4-5 mm. long, pilose 

 on both sides; peduncles 2-4 cm. long, slender; racemes dense, head-like, 1.5-2 cm. long, 1.5 

 cm. in diameter; bracts subulate, 2-3 mm. long; flowers nearly sessile; calyx white-pilose, the 

 tube broadly earnpanulate, 2 mm. long, the teeth subulate, 2 mm. long; corolla apparently 

 white with purple-tipped keel, 5-6 mm. long; banner with an oval blade, strongly arcuate; 

 wings shorter, the blade obliquely oblanceolate; keel-petals nearly as long, the blade lunate, 

 strongly arched at the middle, attenuate at the apex; pod glabrous, 3 mm. long, about as 

 thick, 2 mm. wide, broadly ovate when seen from above, glabrous, acute. 



Type locality: San Luis Obispo. California. 

 Distribution: Known only from the type locality. 



8. Hesperastragalus Elmeri (Greene) Rydb. Bull. Torrey Club 

 53: 168. 1926. 



Astragalus Elmeri Greene, Erythea 3: 98. 1895. 



An annual; stems branched, 2-3 dm. high, with scattered black -hairs; leaves ascending, 

 3-5 cm. long; stipules deltfoid, 4 mm. long, more or less scarious, slightly hairy; leaflets 1 -15, 

 oblong-cuneate, deeply emarginate, 6-10 mm. long, 1.5-3 mm. wide, glabrous above pith 

 scattered white hairs beneath; peduncles 3-6 cm. long; racemes comparatively lax, u ally 

 elongate, 1-2 cm. long, 6-8 mm. thick; bracts subulate, 2 mm. long, black-hairy; calyx b .ck- 

 hairy, the tube earnpanulate, 1 mm. long, the teeth subulate, about 1 mm. long; corolla iilac 

 or white, 3 mm. long; banner obovate, acutish; wings shorter, the blade semi-bastate, the main 

 portion obovate with a long, acute, somewhat porrect auricle; keel-petals as long, the blade 

 almost rectangular, round-truncate at the apex and squarely truncate on the upper edge at 

 the base, the claw broad; pod 3 mm. long and thick, about 2 mm. wide, broadly ovate, as seen 

 from above, reticulate, with appressed white hairs, broadly obcordate in cross-section. 



Type locality: Ross Valley, Marin County. California. 

 Distribution: Central and southern California. 



9. Hesperastragalus compactus A. Heller, Muhlenbergia 2: 218. 1906: 



An annual; stem diffusely branched from the base, 2-3 dm. long, slender, strigose; leaves 

 2-4 cm. long; stipules deltoid, short-acuminate, 2 mm. long, strigose; leaflets 1 1-15, oblong or 

 elliptic, 5-7 mm. long, 2-3 mm. wide, emarginate, strigose on both sides; peduncles 5-8 cm. 

 long; racemes head-like, 7-10 mm. long; flowers subsessile; calyx black-strigose, the tube 1.5 

 mm. long, the teeth subulate; corolla violet-blue; banner obovate, abruptly arched; wings 

 shorter, the blade obliquely oblong; keel-petals still shorter, the blade semi-orbicular, obtuse 

 at the apex, and deeper blue; pods densely strigose with white hairs, cross-ribbed, 4 mm. long, 

 obovoid, the lower suture deeply sulcate, cordate in cross-section, splitting the calyx at matur- 

 ity. 



Type locality: Hills near Pollasky, Fresno County, California. 

 Distribution: Known only from the type locality. 



10. Hesperastragalus Gambellianus (Sheldon) A. Heller, 

 Muhlenbergia 2: 87. 1905. 



Astragalus nigrescens Nutt. Proc. Acad. Phila. 4: 9. 1848. Not .4. nigrescens Pall. 1800. 

 Astragalus Gambellianus Sheldon, Minn. Bot. Stud. 1: 21. 1894. 

 Hesperastragalus nigrescens A. Heller; M. E. Jones, Rev. Astrag. Index. 1923. 



An annual; stems branched at the base, slender, ascending or decumbent, 1-2 dm. high, 

 sparingly pubescent with white hairs, sometimes mixed with black ones; leaves 2-4 cm. long, 



