146 LEGUMINOSJE. Astragalus. 



I. Species with an annual root, all low, mostly small. 

 1. Pod strongly transversely wrinkled, didymous, 2-seeded. 



1. A. didymocarpus, Hook. & Arn. Slender, from 3 inches to a foot high, 

 pubescent with some tine and rather scattered hairs, those of the peduncle and 

 calyx blackish : leaflets 9 to 15, narrowly oblong to linear and more or less cune- 

 ate, deeply notched at the apex : spike an inch or much less in length, close : 



.flowers 1^ to 2^ lines long : corolla white and violet,, its keel inflexed at tip : pod 

 not over two lines long, short-oval and deeply 2-lobed lengthwise so as to be 

 divided into two cells, each nearly filled by the single proportionally large seed. 

 Bot. Beechey, 334, t. 81. A. Catalinensis & A. nigrescens, Nutt. PI. Gamb. 152. 



Low grounds and slopes, common through the western part of the State from Marin Co. south- 

 ward, flowering in spring. Like most annuals varying greatly in size and robustness. 



2. Pod not wrinkled, few many-seeded. 



* Calyx blackish-hairy, much shorter than the violet or white and violet-tipped corolla : 

 pod not inflated, between oblong and linear : flowers few and nearly sessile, crowded 

 in a small head which does not lengthen in fruit. 



2. A. tener, Gray. Slender, a span or so in height, sparsely and minutely 

 pubescent : leaflets 9 to 15, linear or cuneate-linear, with or without a retuse or 

 notched apex : head 5 9-flowered : pod between coriaceous and cartilaginous, 

 about half an inch long, 2-celled, 5 10-seeded. Proc. Am. Acad. vi. 206. 

 Phaca astragalina, var., Hook. & Arn. Bot. Beechey, 334. Astragalus Hypoglottis, 

 var. strigosa, Kellogg, Proc. Calif. Acad. ii. 115, fig. 37. 



Moist grounds, common around San Francisco Bay, &c. Corolla 4 or 5 lines long, often bright 

 violet, sometimes pale and violet-tipped. 



3. A. Breweri, Gray, 1. c. Much like the preceding : leaflets broader, oblong- 

 obcordate : forming pod more ovate, 6-ovuled, and 1 -celled or nearly so. 



Sonoma Valley, common in fields, Brewer. Not since met with ; the fruit unknown. Per- 

 haps not distinct from the preceding. 



* * Calyx whitish-haired or nearly so : pod linear : flowers few and crowded at the 



apex of the peduncle. 



4. A. Nuttallianus, DC. More or less pubescent or hoary with white ap- 

 pressed hairs, soon diffusely branched from the base: leaflets 11 or 13, oblong or 

 broadly linear and mostly notched at the end : calyx-teeth slender and as 1 ng as 

 the tube : corolla whitish and purple, about 3 lines long ; the keel with the inflexed 

 tip narrowed : pod over half an inch long, laterally flattish, slightly scythe-shaped, 

 the incurvation mostly near the base, deeply grooved on the back, acutish on the 

 other edge, 2-celled, several-seeded; the surface minutely reticulated, either glabrous 

 or with minute appressed hairs. 



Southeastern borders of the State (on the Rio Colorado, Newlerry), and east to Texas and 

 Arkansas. 



* * * Calyx white-pubescent or canescent : pod ovate and in fated : flowers racemose. 



5. A Greyeri, Gray. Strigosely somewhat hoary, branching from the base, a 

 span high : leaflets 7 to 11, linear, less than half an inch long: raceme 3-7-flowered: 

 corolla yellowish-white, 3 lines long : pod thin-bladdery, half an inch long, very 

 oblique and the acute tip incurved, minutely hoary-pubescent, 1 -celled, many-seeded. 

 Phaca annua, Geyer. 



W. Nevada, not far from the boundary ( Watsov) ; thence east to Wyoming, Gcyer, Parry. 



6. A. Coulteri, Benth. A span to a foot high, stouter, tomentose-canesceut or 

 the leaves silvery-silky : leaflets 9 to 19, obovate or oblong, sometimes emarginate, 

 3 to 5 lines long: raceme or spike loosely 10- 20-flowered : calyx-teeth shorter 



