1923] Ottley: A Revisio7i of the Calif ornian Species of Lotus 197 



Legumes linear; bracts, when present, mostly of 1 to 3 leaflets closely associated 

 with the umbel; pedicels short, rarely over 1 mm. long. 



Glabrous or nearly so; flowers 1.3 to 2 cm. long; claws of the petals dis- 

 tinctly exserted beyong the calyx tube, those of the keel longer than 

 the narrowly beaked blade. 



Bract absent as a rule; flowers yellow and white or cream-color 



_ 4, L. pinnatus. 



Bract of 1 to 3 leaflets; banner yellow, wings pale rose or lilac, tip of 

 keel purple 5. L. formosissimus. 



Hirsute-pubescent to nearly glabrous; flowers 7 mm. to 1.5 cm. long; claws 

 of the petals obscurely exserted beyong calyx tube, those of the keel 



only about one-half the length of the broad rounded blade 



6. L. oblongifolius. 



Subgenus 2. Acmispon. Annuals or perennials; leaves pinnate 

 or in a few species subpalmate, short (except in L. grandiflorus) ; 

 stipules gland-like ; flowers 4 mm. to 2.5 cm. long, solitary or umbellate, 

 mostly peduncled ; legumes dehiscent, straight or nearly so, abruptly 

 short-beaked, two to many-seeded, not reflexed. 



Stigma capitate with a collar of spreading hairs below it; wings conspicuously 

 longer than the keel, canoe-shaped, one beneath, the other inverted over 

 the keel; banner blade attenuate into the claw. 



Perennials; umbels pedunculate, one to many-flowered. 



Leaf rachis elongated; flowers 1.3 to 2.5 cm. long; umbels mostly several- 

 flowered 7. L. grandiflorus. 



Rachis short, bearing few leaflets, leaves often subpalmate; umbels 1 to 



3 (to 5)-flowered. 



Plant erect; stems stiff, internodes long: leaves small; flowers 1.3 cm. 



to 2.2 cm. long; legumes typically straw-colored, terete, 2 to 



5 cm. long by 3 to 5 mm. -wide, many-seeded; seeds granulose. 



8. L. rigidus. 



Plants procumbent to ascending; internodes not conspicuously long; 



seeds not granulose but occasionally shallow-pitted. 



Legumes mostly reddish brown, appressed-pubescent, 2.5 mm. or less 



A^•ide ; flowers 8 to 10 mm. long..9. L. wrightii var. multicaulis. 



Legumes mostly straw-colored, thinly silky-pubescent, 1 to 2.2 cm. 



long, 2 to 4 mm. wide; flowers 8 to 12 mm. long 



10. L. argyraeus. 



Annuals; umbels pedunculate, 1 to 3-flowered. 



Seeds quadrate, granulose, sometimes rugose 11. L. strigosus. 



Seeds subglobose, granulose, sometimes rugose 12. L. tnmentellus. 



Stigma capitate but without the collar of hairs; wings of about the same length 

 as the keel, more or less strap-shaped, one on either side of the keel; 

 banner blade abruptly clawed; flowers not over 1.2 cm. long; annuals. 



Seeds orbicular to short-oblong, ends always rounded; legumes linear; flowers 

 peduncled (except in variety of L. americanus) . 



Leaf rachis dilated; umbels 1 to 5-flowered; keel obtuse, not attenuately 

 beaked 13. L. salsuginosus. 



