CRUCIFER^E. . 3i 



latter ; the stigma is simple and very small, on a tapering style, 

 nearly a line in length ; neither is the plant so acrid, being ra- 

 ther bitter to the taste. See Darlington's Florula Cestrica, and 

 his paper in Sill. Amer. Jour. xvii. 356. 



3. C. bettidifoUa Linn. : leaves glabrous, somewhat fleshy ; radical 

 ones petioled, ovate, entire; cauline ones few, entire, or somewhat 3- 

 lobed ; pod erect ; stigma subsessile. C, rotundifolia ? Big. 



HAB. Highest summit of the White mountains, Rocky moun- 

 tains, and throughout Arctic America. July. If. I received 

 a specimen of this plant from my friend Dr. Charles Pickering 

 of Philadelphia, who obtained it from the first named locality, 

 The stem is simple and apparently procumbent, 4 5 inches 

 long. Lower leaves 1-2 3-4 of an inch in length, ovate or sub- 

 orbicular, on long slender petioles. Pod an inch long, surmount^ 

 ed by a short style. It is very near C. alpina. . 



>;. ** Leaves divided. . 



4. C. pratensis Linn.: leaves pinnate; leafets of the radical ones 

 roundish, of the cauline ones linear or lanceolate, entire ; flowers 

 large, in a terminal corymb ; style very short, nearly as thick as the 

 pod ; stigma capitate. 



HAB. Woods. N. S. and throughout Arctic America. June. 

 If. Stem 10 12 inches high. Flowers purplish, large. Pod 

 linear, nearly an inch long. This species can be readily distin-? 

 guished by its large flowers and thick style. 



5. C, hirsute, Linn, .* leaves pinnate; leafets of the radical ones petiol- 

 ed, mostly rounded; of the cauline ones lanceolate, subpetioled, dentate 

 or very entire ; petals small, oblong-cuneate ; stigma minute, subses- 

 sile. C. pennsylvanica Muhl. De Cand. C. virginiana Linn. 



HAB. Wet grounds. Throughout the U. S. and Can. July. 0. 

 I adopt the views of Dr. Hooker concerning this species. I 

 have never been able to ascertain the specific line between the 

 C. pennsylvanica and C. virginica of American botanists ; hav- 

 ing seen every variety in the size, form of the leaves, and direc- 

 tion of the stem, of these supposed distinct plants. The present 

 species is very extensively distributed, American Water-cress. 



6. C. tares Mich. : leaves sublyrate-pinnatifid, segments oval-oblong, 

 the terminal one somewhat 3-lobed ; pod short, erect, terete. . 



HAB. Low grounds. N. Eng. to N. J. Pursh. June, July. 

 If. De Candolle thinks this may belong to his genus Nastur- 

 tium, 



16. NASTURTIUM. Brown. 



Pod rounded (sometimes short.) Stigma sub-2-lobed. 

 Valves concave, nerveless, not keeled. Cotyledons accumbenf. 

 Calyx spreading. Tetradynamia. Siliquosa. 



1. N. officinale Brown: leaves pinnate ; leafets ovate, subcordate, 

 innate-dentate ; upper ones pinnatifid. Sisymbrum Nasturtium Linn. 





