37 Rydberg : Studies ox the Rocky Mountain Flora 



white-silky villous ; lobes very short, about 2 mm. long : corolla 

 ochroleucous without any purple, 12-15 ^m- long: keel very 

 short and round, abruptly tipped with a small tip : pod thin, per- 

 fectly 2-celled, white-silky, about 1.5 cm. long, more than twice as 

 long as the calyx, tipped with a slender beak which is abruptly 

 hooked at the ape.x. 



This belongs to the A. campcstris group and is characterized 

 by the coarse spreading pubescence of the scape and the ochro- 

 leucous flowers without any trace of purple. 



Montana : Craig, 1900, E. V. Wilcox, jyS (type in U. S. Nat. 

 Herb.). 



Trifolium lilacinum sp. nov. 



A densely cespitose dwarf subscapose perennial with very deep 

 root. The short branches of the caudex covered with the scarious 

 stipules and remains of old leaves : leaves 3-foliolate, bright green ; 

 petioles 2—6 cm. long, strigose : leaflets elliptic or lanceolate-ob- 

 long, acute at each end, 1-2.5 cm. long, strigose : peduncle 5-12 

 cm. long, bracts minute, less than i mm. long, 3-toothed : flowers 

 reflexed in fruit : calyx densely strigose ; tube 3 mm. long ; teeth 

 subulate-filiform, 4-6 mm. long : corolla pale rose-purple or lilac, 

 in age turning light brownish, about i cm. long ; banner straight 

 and obtuse. 



This species is related to T. dasypliylluiii ; differing in the 

 minute 3-toothed bracts and their shorter and comparatively 

 broader leaflets. It is still nearer related to T. aaiminatus Greene ; 

 from which it is distinguished by the smaller flowers and the not 

 acuminate banner. It is an alpine plant growing among rocks at 

 an altitude of about 3000 m. 



Colorado: West Spanish Peak, 1900, Rydberg & Vrec/and, 

 j()30 (type), S951 and 3932. 



Lathyrus leucanthus sp. nov. 



A glabrous or slightly pubescent perennial with a very slender 

 rootstock. Stem about 3 dm. high, angled : stipules very narrow, 

 semi -sagittate : leaflets 2—4 pairs, elliptic, veiny, glaucous, acute, 

 mucronate, 1—3 cm. long, 3— 10 mm. wide : tendrils of the lower 

 leaves mere tips ; of the upper elongated and sometimes 3 -di- 

 vided : racemes short, in the axils of the middle leaves, 3—4 cm. 

 long, 2— 4-flowered : calyx glabrous, cleft to about the middle : 

 lobes lanceolate, acuminate: corolla white, about 15 mm. long: 

 banner broad. 



