ORDER 11.-CRUCIFERJ2. 37 



4. ARABIS, L. ROCK-CRESS. Sepals mostly erect; silique linear, com- 

 pressed ; valves plane, each with 1 or 3 longitudinal veins, seeds in a sin- 

 gle row in each cell, mostly margined, cotyledons accumbent or oblique. 

 Flowers white. Figs. 336, 506. 



* Loaves (all or at least the radical) pinnatifld. Stems clustered Nos. J, 2, 8 



* Leave* all undivided, toothed or entire, often clasping.. (a) (Exotic. No. 10.) 



a Siliques short (6 12") and straight. Sds. not winged. Stems clustered.. NOB. 4, f. 

 a Siliques longer (120. straight or curved. Sds. not winged. St. simple. .Nos. 6. 7 



a Siliques .ong V 3'), curved, pendent. Seeds winged Nos 8, 9 



1 A* Ijudoviciaiia Meyer. All the leaves pinnatifid or pinnate, gmoorhish ; Kcma 

 branched at base ; siliques ascending ; seeds bordered. (D South. 6 KX. March. 



3 A. lyrata L. Upper leaves smooth, linear, entire ; radical leaves lyrately pinnatifid. 



often pilous ; st. branched at base ; pedicels spreading ; siliques erect, peede not bor- 

 dered, obliquely o . (a) Hills, Can.toVa. 612'. Pods H V. Pet. 3" long. Apr., May. 

 8 A. petraea Lam. Upper leaves linear, entire, minute, radical pinnatifid, very small ; 

 steins clustered ; pods ascending (1 HO ; seeds bordered, o . ii Rocks (Green- 

 wich), Ct., Vt., O., Mich. 6 12'. Flowers white or roseate. June. 



4 A. Thaliaiia L. St. clustered, erect ; Ivs. pilous, oblong, nearly entire ; pet. twice 



longer than calyx ; perls erect, squarish (9") ; seeds obliquely II o . Fields, Vt. to 111. 

 and Car. (Wayne Co., N. Y. Hankenson.) 4-12'. Fls. small. May. (Sisymbrium, Gay.) 



5 A. deiitata T. & G. Stems clustered, diffuse ; Ivs. oblong, sharply toothed ; petals 



hardly longer than the calyx ; pods spreading. (5) N. Y. to Mo. If. Fls. small. May. 



6 A. patens Still. Erect, pubescent ; cauline leaves coarsely toothed ; siliques spread- 



ing and curved upward, beaked with a distinct style. @ O. to Tenn. 1 2f. May. 



7 A. hirsuta Scop. Erect, hirsute; radical leaves oblong-ovate, canline lanceolate, 



sagittate-clasping, entire or toothed ; siliques straight, erect ; style none, @ Can. to 

 Va., and W. 1 2f. June. 



8 A. Iji-viiiata DC. Tall, glaucous, smooth ; stem leave? linear-lanceolate and linear, 



sagittate-clasping, the upper entire : siliques very long, linear, at length spreading 

 and pendulous. Can. to Tenn., and W. 2f. Pod 3'. May. 

 j3. minor (Porter). Plant smaller, 1015', with the Ivs. sessile not clasping. Penn. 



9 A. Cauadeiisis L. Sickle-pod. Tall, pubescent ; stem leaves lanceolate, pointed 



both ways, sessile ; silique subfalcate, veined, pendulous. Rocky hills. 2 3f. 

 Petals small, but twice longer than sepals. Pods 3'. May, June. 



10 A. ALPINA. Erect, 8 >2', hoary with stellate hairs ; Ivs. oblong, with slender teeth, 

 clasping ; fls. showy, pure wh., in many little long-stalked corymbs. Alps. Mar. May. 



5. CARDAMINB, L. BITTER CRESS. Calyx a little spreading. Sil- 

 ique linear or lanceolate, with flat, veinless valves narrower than the dis- 

 sepiment, and often opening elastically from the base. Stigma entire. 

 Seeds not margined, = o . Flowers white or purple. 



DENTARIA. Pod lance-linear. Rhizome thickish, knotted. Stem with 2 or 3 palmated 

 leaves near the middle. Flowers large, corymbed. . .(*) 



* Leaves of the stem subopposite or subverticillate Nos. 1, 2. 3 



* Leaves of the stem alternate Nos. 1. 5 



| CARDA.MINK. Pod linear. Root tuberous or fibrous. Leaves alternate...^) 



t Leaves pinnate, with many leaflets Nos. 6, T 



t Leaves simple or partly ternate. . . (a) 



a Siliques pointed with a slender style. In low, wet grounds Nos. 8, 9 



a Siliques tipped with the sessile stigma. In high mountains Nos. 10, 1 1 



1 C. dipliylla. Stem 2-leaved ; leaflets subovate ; rhizome continuous, toothed. 

 ii Damp wood?. Can. to Car. If. Leaves 3-parted, nearly opposite. Root-stock 

 pungent, aromatic. May. 



