106 CRUCIFER^. Draba. 



linear, and, with the pedicels, glabrous. DC. syst. 2. p. 346 ; Deless. ic. 2. t. 

 46./. A; Hook.fl. Bur.-Am. 1. p. 53. 



Rocky Mountains, lat. 52^-57°. — Flowers white. Silicles 6 lines long and 

 scarcely one line wide. DC. 



16. D. crassifolia (Graham); scape naked or with a single leaf; calyx 

 and pedicels glabrous ; leaves linear -spatulate, somewhat fleshy, ciliate with 

 simple hairs ; petals a little exceeding the calyx, retuse ; silicles ovate-ellipti- 

 cal, glabrous. — Graham, in Edinb. pjiil. jour. 1829.^3. 182; Hook. ! fl. Bor.- 

 Am. 1. p. 54. 



o. petals white. Hook. I, c. 



0. petals pale yellow. Hook. I. c. 



Summits of the Rocky Mountains, lat 52^-57°, Drummond ! and about 

 lat. 41°, Nuttall. — Scapes 1-2 inches high : flowers small. Silicles glabrous. 

 Hook. Leaves lanceolate-linear, entire or somewhat serrate. Nutt. 



* * Perennial : stems leafy. 



17. D. ? Icevigata (Cham. & Schlecht.) : stem leafy, simple, glabrous, 

 strict ; radical and inferior cauline leaves petioled, ovate, attenuate at the 

 base, somewhat fleshy, the margin obscurely ciliate ; silicles oblong-lanceolate, 

 glabrous, 4-6 times as long as the pedicels. Cham. ^ Schlecht. in Linncea, 

 1. p. 25 ; Hook. Jl. Bor.-Am. 1. p. 54. 



Island of St. Lawrence, Chamisso. — Root thick, descending. Radical 

 leaves few, (not in a rosulate cluster) with the petiole 1^-2 inches long. — 

 Stems several, 3-4 inches high in flower, elongated in fruit. Flowers white. 

 Silicles 7-8 lines long, and 3-4ths of a line broad : style very short. Seeds 

 not seen. Cham. ^ Schlecht. — Hooker has placed this in his second section, 

 including the annual and biennial species ; but the authors above quoted state 

 it to be perennial. 



18. D. ramosissima (Desv.) : puberulent ; stems numerous ; leaves linear- 

 lanceolate, remotely and sharply laciniate-toothed ; racemes corymbosely 

 panicidate ; silicles lanceolate, attenuate at each end, pubescent ; style one- 

 fourth the length of the silicle. — Desv. jour. bot. 3. p. 168; DC. syst. 2. p. 

 355 ; Gray ! in ann. lye. New- York., 3. p. 224. D. arabisans, Pursh ! fl. 2. p. 

 434. (not of Michx.) D. dentata. Hook. ^ Am. ! in jour. bot. 1. p. 192 

 (without descr.); Hook.! ic. \.t. 31. Alyssum dentatum, Nutt.! gen. 2. 

 p. 63. 



On rocks, Harper's Ferry, Virginia ! and Cliffs of Kentucky River, Short! 

 April-May. — Rhizoma creeping, branching and throwing up tufts of stems, 

 which are about a span high. Pubescence simple and stellate (mostly with 

 4 rays). Radical leaves rosulate, crowded, with a long cuneiform base; cau- 

 line ones sessile, almost pectinateiy toothed; the teeth 2-3 on each side. 

 Racemes forming a large spreading panicle : flowers white. Pedicels erect- 

 spreading, about as long as the somewhat contorted silicle. Seeds 4-7 in each 

 cell. — A very distinct species, with much the habit of D. arabisans. 



19. D. arabisans (Michx.) : slightly and stellately pubescent ; stem leafy, 

 simple or branching from the base, leaves acutely toothed, radical ones cune- 

 ate-lanceolate, the cauline oblong; silicles glabrous, lanceolate-oblong, acumi- 

 nate with a very short but distinct style ; petals (Avhite) about twice as long 

 as the sepals.— Mic/i.r. .' /. 2. p. 28 ; DC. prodr. 1. p. 170 ; Hook. ft. Bor.- 

 Am. 1. p. 55. D. incana /?. glabriuscula, Gray ! in ann. lye. New- York, 3. 

 p. 223. 



/?. leaves nearly entire, radical ones rather obtuse ; style almost wanting. — 

 D. Longii, herb. Schwein. ! ; Nutt. ! onss. 



Rocks, Lake Champlain, Michaux ! and on the borders of small lakes in 

 the northern part of the State of New York ! /?. Fort Gratiot, and N. shore 



