TnRRiTis. XIII. CRUCIFERtE. 165 



1. N. OFFiciNALK. R.Br. (SispnbriumNast. I/iw(.) EnglishWaler Cress. 

 Lvs. pinnate ; Ifts. ovate, subcordate, repand ; fet. white, longer than tlie 



calyx.— '4- Brooks and ponds. Stems decumbent, 11" long, thick, with axillary- 

 branches. Leaves ot:^ — 7 leaflets; leaflets broad, often cordate, rather acute, 

 obtusely toothed, terminal one largest. Flowers corymbed. Siliques less than 

 1' long. Jn.— It is beginning to be cultivated in the vicinity of our cities as a 

 salad. ^1 



2. N. AMpniBirM. R. Br. (Sisymbrium. Linn.) Amphibious Water Cress. 

 Lvs. oblong-lanceolate, pinnatifidor serrate; rt. fibrous ;/>«/. longer than 



the calyx; siliquc elliptical, acute at base, tipped with the mucronate style.— 

 % Banks of the Mohawk, Dr. Robhins. Rare. Stem 1— 2f high, furrowed. 

 Leaves variable, immersed ones pinnatifid or pectinate, upper ones serrate. 

 Flowers yellow, minute, in a long, dense raceme. Siliquc half as long as the 

 spreading or reflexed peduncle, pointed with the short style. Jn. Jl. 



3. N. PALL-.STRE. DC. Marsh Water Cress. 



Lis. pinnately lobed, amplexicaul, lobes confluent, dentate, smooth; rt. 

 fusiform ; pel. as long as the sepals ; silique spreading, turgid, obtuse at each 

 end.— T; In wet places. Stem 1— "if high, erect, branched above. Leaves a— 3 

 long, all more or less pinnatifid, smooth, except a few ciliae at base. Flowers 

 numerous, minute, yellow. Siliquc 3 — \" long, on pedicels of equal length, 

 Jn. — Aug. 



4. N. HispiDUM. DC. (Si.symbrium. Poiret.) Hispid Water Cress. 



St. villous ; /i-5. somewhat villous, runcinate-pinnatifid, lobes rather ob- 

 tusely dentate ; sili(jucs (rather silicles) ovate, tumid, pointed with the style, 

 scarcely more than half as long as the pedicels; pet. scarcely as long as the 

 calyx.— '4 Banks of streams, Walpole, N. H., Conn, to Fenn. Stem angular, 

 branched, 1— 3f high, with many paniculate racemes above. Leaves 3 — 6 

 long. Flowers minute, yellow. Silicles I" long, on pedicels 2—3" long and 

 somewhat spreading. 



5. N. NATANS. DC. /?. Avicricaimm. Gray. Floating Water Cress. 

 Emcrscd lvs. serrate, oblong-linear, undivided, immersed ones doubly 



pinnatifid, with capillary segments ; pet. twice as long as the calyx ; sihques 

 obovate, twice as long as the style.— TJ. In water. Can. and U. S. Stem long, 

 submerged. Flowers white, middle size. Jl. 



G. N. sYLVK.^^TKE. (Sisymbrium vulgarc. Pers.') Creeping Water Cress. 



Lvs. pinnately divided, segments lanceolate, incisely atrvaXe.; pet. longer 

 than the calyx; siliques oblong, torulose; sty. very short.— Banks ol the Dela- 

 ware near Philadelphia. Nuttall. § 



13. BARB ARE A. R. Br. 



In honor of St. Barbara, who discovered (what no one has since perceived) its medicinal virtuea. 



Sepals erect, subequal at base ; silique columnar, 2— 4-coriiered : 

 valves concave-carinate ; seeds in a single series ; 0=. — Lvs. lyrately 

 pinnatifid. Fls. yellow. 



B. VULGARIS. R. Br. (Erysimum Barbarea. Linn.) Winter Cress. 



LoiL-er lvs. Ivrate, the terminal lobe roundish, vpper ones obovate, pin- 

 natifid at base, crenate or repand-dentate ; siliqtics obscurely 4-cornered.--T; In 

 old fields, also brook-sides, Northern States, W. to Oregon, common. vVhole 

 plant glabrous. Stem furrowed, 1— 2f high, branching above. Leaves 1— •.>— 4 

 Ion?, dark green, shining, on cla.sping petioles, the terminal lobe 1— li diam., 

 upper ones sessile, all with obtuse teeth. Flowers on pedicels \ long, in ter- 

 minal racemes. Siliques slender, V long, curved upwards. May, Jn. 



14. TURRITIS. Dillon. 



I.nt. IvrritJs, turrcted ; from the pj-ramidal form of the plant. 



Sepals erect, converging ; petals erect ; silique long, linear, 2-edged ; 

 valves plane : seeds in a double scries, 0=. — Fls. cyanic. 



