486 FABACEAE 



M. Arborei. 



Stems erect or ascending. 



Leaflets commonly 5 cm. long, permanently subsilky above; seeds without pale spots at the micropyle. 



61. L. longifolius. 

 Leaflets usually less than 4 cm. long, or plant not a shrub. 



Plants usually true shrubs; seeds 4-6 mm. long, with a pair of contiguous pale spots embracing the 



micropyle. 62. L. arboreus. 



Plants strictly herbaceous, or suffrutescent only at base; seeds about 3 mm. long, without pale spots at 

 the micropyle. 

 Floral bracts mostly persistent and villous; leaves more or less villous on both sides. 



67. L. Coiillei. 

 Floral bracts deciduous; leaves glabrous or glabrate above. 



Leaflets linear, with long-petioled lower leaves at flowering time. 68. L. gracilentus. 



Leaflets oblanceolate, without long-petioled leaves at flowering time. 63. L. rivularis. 

 Stems usually decumbent at base, where more or less woody. 

 Roots not bright yellow. 



Stems 4-6 mm. thick; most of the petioles about equaling their leaflets. 63. L. rivularis. 



Stems 2-3 mm. thick; most or all of the petioles 2-3 times as long as their leaflets. 



64. L. variicolor. 



Roots bright yellow. 



Leaflets 5-9, greenish; stems usually with some spreading hairs; ovules 9-14. 65. L. littoralis. 



Leaflets 3-5, silvery-silky; stems appressed-pubescent; ovules 5-8. 66. L. Tidestromii. 



N. Albicaules. 



Banner narrow, acute at apex, median line much curved in bud; wings narrow and keel much exposed. 



69. L. albicaulis. 



Banner ovate to suborbicular, usually obtuse or rounded at apex; wings wider and keel largely or entirely covered. 



Stipules foliaceous, green, lanceolate, oblanceolate, elliptic, or oval. 



Stipules subulate or linear, not leaf-like. 



Leaflets greenish, not silky, sometimes glabrate above. 



Flowers 8—14 mm. long. 



Stems sparsely appressed-pubescent. 



Stems shortly spreading-pubescent. 



Flowers 14—18 mm. long. 



Petals consistently all cream-colored or yellow. 



Petals blue or purple, only the center of banner yellow. 



Leaflets densely pubescent, grayish, whitish, or silvery, more or less silky. 



Flowers 14-18 mm. long. 75. L. formosus. 



Flowers 8-14 mm. long. 



Plants 5-9 dm. tall; leaflets silvery-silky above, often duller below. 73. L. elatus. 



Plants 2-5 dm. tall; leaflets not silvery-silky above. 



Stems and petioles mostly appressed-pubescent. 74. L. adsurgens var. 



Stems and petioles largely spreading-pubescent. 75. L. formosus var. 



O. Latifolii. 

 One species. 76 - L. latifolius. 



P. POLYPHYLLI. 



Floral bracts persistent or tardily deciduous; pedicels spreading-pubescent; leaflets 5-9. 

 Floral bracts early deciduous; pedicels commonly appressed-pubescent. 



Leaflets 5-9, rarely 10, usually not over 8 cm. long. 



Leaflets 10-17, 6-15 cm. long. 



Q. Saxosi. 



Leaves silvery-silky above. 



Leaves green, glabrous to loosely villous or sparsely appressed-pubescent above. 



Petioles 2-4 cm. long; flowers 10-12 mm. long; stems and leaves conspicuously villous. 



81. L. volcanicus. 

 Petioles 5-30 cm. long. 



Largest leaflets 2—4 cm. long; longest petioles usually less than 10 cm. long. 82. L. saxosus. 



Largest leaflets 5-8 cm. long; longest petioles usually 10-30 cm. long. S3. L. arcticus. 



R. Magnifici. 



One species. 84. L. magnificus. 



1. Lupinus horizontalis Heller. Sunset Platycarpos. Fig. 2560. 



Lupinus horizontalis Heller, Muhlenbergia 2: 74. 1905. 



Pubescent with short spreading hairs, 10-12 cm. tall, branched, the lower branches prostrate, 

 all floriferous. Leaves long-petioled, glabrous above, petioles 4-6 cm. long, leaflets 7-9, ob- 

 lanceolate, 1-2 cm. long; peduncles 3-4 cm. long, racemes 5-8 cm. long, equaling or surpassing 

 the foliage ; flowers about 10 mm. long, ascending to suberect, whorled, bracts persistent, re- 

 flexed, pedicels 1-2 mm. long; calyx pubescent, upper lip cleft, lower_ bidentate ; petals pale 

 violet-blue, banner almost plane, about 7 mm. wide, wings 4-5 mm. wide, keel straight, both 

 wings and keel ciliate on both upper and lower edges near claws ; pods ovate, villous, 12 mm. 

 long, ovules 2, seeds 3 mm. long, marked with small dark spots. 



Dry gravelly hillsides, Lower Sonoran Zone; known only from the original collection. Type locality: Sunset, 

 Kern County, California. April. 



Lupinus horizontalis var. platypetalus C. P. Smith, Bull. Torrey Club 45: 12. 1918. Branches all as- 

 cending; flowers 13-15 mm. long, banner 11-12 mm. wide, its sides reflexed^ wings 6-7 mm. wide. Desert sands, 

 at the base of the mountains, northern San Bernardino and northeastern Kern Counties, California; Lower So- 

 noran Zone. Type locality: eastern base of Fremont's Peak, San Bernardino County, California. 



