30 CRUCIFER^. 



Wet grounds near springs, Can. to Car. July. %. — Stem 6 — 15 inches liigh, 

 decumbent. Flowers in terminal racemes, white, or yellowish, half the size of 

 the preceding. The taste of the root is rather bitter than acrid, as in that of C. 

 rhomboidea. Quite distinct. Round-leaved Cardamine. 



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

 petioled, ovate, entire ; cauline few, entire, or somewhat 3-lobed ; pod erect ; 

 stigma subsessile, C. rotundifolia Big. 



Highest summit of the White Mountains, Rocky Mountains, and throughout 

 Arctic America. July. %. — Plant 2— A inches high. Flowers in a corymbed 

 raceme. Petals cuneiform, twice as long as the calyx, white. Pod an inch long, 

 surmounted by a short style. Allied to C. alpina. Mountain Cardamine. 



** Leaves divided. 



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

 ish ; of the cauline, linear or lanceolate, entire ; flowers large, in a terminal 

 corymb ; style very short, nearly as thick as the pod ; stigma capitate. 



Swamps. Arct. and N. W. America to Western N. Y. June. %. — Stem 

 13 — 18 inches high. Flowers purplish, large. Pod linear, an inch long. This 

 species can be readily distinguished by its large flowers and thick style. 



Common Bitter Cress. 



5. C hirsuta Linn. : leaves pinnate ; leafets of the radical ones petioled, 

 mostly rounded ; of the cauline ovate or linear, toothed or entire ; petals 

 small, oblong-cuneate ; stigma minute, subsessile. C.Pennsylvanica Muhl. 

 D. C. C. Virginica Mich. 



Wet grounds. Throughout the U. S. and Can. to Arct. and N, W. Amer. 

 July. (1) — From 4 inches to a foot or more in height. Leaves hairy or smooth. 

 Flowers small, white. A very variable species. American Water Cress. 



6. C. teres Mich. : leaves sublyrate-pinnatifid ; segments oval-oblong, the 

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



Low grounds. N. Eng. to N. J. Pursh. June, July. %. — Stem slender, 

 erect, branching. Pod on a short pedicel. De Candolle thinks this may belong 

 to his gen\is Nasturtium ; while Torrey and Gray place it, with a mark of doubt, 

 in the genus Sisymbrium. Terete Cardamine. 



15. NASTURTIUM. Brmcn.— Cress. 



(From Nasvs tortus, a convulsed nose, an effect supposed to be produced by the 

 acrid and pungent quaUty of this plant.) 



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



concave, nerveless, not keeled. Cotyledons accumbent. Calyx 



spreading. 



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

 ate-dentate ; upper ones pinnatifid. Sisymbrium Nasturtium Linn. 



In water. Throughout the U. S. and to the N. W. coast. June, July. %. — 

 Stem decumbent, floating. Leaves large. Flowers white, corymbed. Pod about 

 an inch long. Esteemed as a salad. Water Cress. 



2. N. palustre D. C: root fibrous; leaves lyrate-pinnatifid : lobes con- 

 fluent, unequally toothed, smooth ; petals as long as the calyx ; pod obtuse 

 at both ends, turgid. Sisymbrium palustre Willd. 



Wet places, throughout the U. S. and to the shores of the Arctic sea. July. 

 ®. — Stem 18 inches high, mostly erect, branched. Jjeaves glabrous, all more or 

 less puuiatifid. Flowers numerous, minute, yellow. Pod short, turgid. 



Marsh Cress. 



