270 



LEUUMINOSAE 



broad) ; flowers 5 to G lines lonji;; pedicels stout, ^/^ line long; calyx white-silky, the 

 upper lip shortly bifid, the lower entire, rounded at apex; petals yellow; banner 

 glabrous, emarginate at apex; keel straight, very broad (2 lines wide), ciliate at 

 the middle or above, the acumen very short and blunt; ovules 3 to 5; fruit unknown. 



Loose rockj'^ soil in canons: desert .slope of the San Gabriel I\Its. (Rock Creek, 

 4250 feet). Apr. So far jus known, a highly localized and well-marked endemic. 



Ref. — Lupin us peirsonii Mason, Madrono 1:187 (1928), type loc. Rock Creek cafion, n. 

 slope San Gabriel Mts., Mason 3026. 



31. L. leucophyllus Dougl. Poison Lupine. (Fig. 187.) Plants IV2 to 3 

 feet high, the stems stout, leafy, few or several from a branched rogt-crown; stem 

 and petioles shaggj'^-tomentose, the leaflets densely silky-velvety; stipules subu- 

 late; leaflets 7 to 10, oblance- 

 olate, acute, 1 to 2% inches 

 long; the lower petioles 3 to 9 

 inches long, the uppermost 

 about equaling or shorter than 

 the leaflets; racemes dense, I/2 

 to 1 foot long, usually shortly 

 or not at all peduncled; flowers 

 4 to 6 lines long, in more or 

 less indistinct whorls; pedicels 

 stout, 1 to 11/2 lines long; calyx 

 subsaccate at base on upper 

 side; lower lip minutely 3- 

 toothed at apex, longer than the 

 deeply cleft upper lip; petals 

 blue, pink or dingy lavender; 

 banner villous on the back, 

 shorter than the wings; keel cili- 

 ate; pods % to 1% inches long, 

 silky, 4-seeded. 



Dry valleys or montane sum- 

 mits, often in red gravelly or 

 volcanic soil, 2700 to 5300 feet : 

 western Colusa Co. to Shasta 

 and Siskiyou Cos., thence east 

 to Lassen Co. Eastern Wash- 

 ington and Oregon to New Mex- 

 ico. ]\Iay-July. 



Note on variation. — Variation in 

 Lupinus leucophyllus does not well 

 lend itself to definite segregation into 

 named forms. The pubescence varies 

 in length and density rather than in 

 character. The northern plant origi- 

 nally described was apparently simi- 

 lar to Trinity County specimens, the 

 short villous or sub-tomentose layer 

 almost obscured by long spreading 

 hairs. In most specimens of var. belliae C. P. Sm., the long hairs are less abundant and in var. 

 canescens C. P. Sm. are absent. The bracts are either longer or shorter than the calyx. The 

 form called L. plumosus Dougl. is conspicuously long-bracted, and in the illustration accompany- 

 ing the original description of L. leucophyllus Dougl. the bracts are evident. The plants are also 

 quite easily segregated into many larger- and smaller-flowered races, the latter more common 

 interiorly. Flower size is, however, not associated constantly with other characters, the result 

 being that the requirements described for var. belliae C. P. Sm. bring together unlike races 

 canescens C. P. Sm. combines three segregating characters and is here accepted. 



Fig. 187. Lupinus leucophyllus Dougl. a, habit, 

 X l^; b, calyx, X 1^/^; c, banner, X 1%; d, wing, X 

 IVa ; e, keel, X 1% ; /, pod, X 1. 



Var. 



