74 CRUCIFER^l^. Nasturtium. 



rate ; root fibrous ; petals lonj^er than the calyx ; silique ellipsoid, spreading', 

 mucronate with the style. DC. prodr. 1. p. 138; Honk. fl. Bur. -Am. \.p. 

 39. Sisymbrium amphibiurn, TAnn. ; Ptirsh, fi. 2. p. 440. 



Watery places; Canada, i/oo/cer; Pennsylvania to Virs^inia, Pursh. — 

 Stems sulcate, sparingly branched. Ernersed leaves serrate, often pubescent; 

 immersed ones more or less pinnately lobed, sometimes pectinately capillace- 

 ous. Racemes dense, elongated. Peduncles spreading, at length rtflexed, 

 twice as long as the silique. Silique oblong-ovate, attenuate at the base, 

 pointed with the short style. DC. — We have seen no N. American speci- 

 mens that accord with the description of this plant. The N. amphibiurn of 

 some of our botanists is probably only a variety of N. palustre. 



9. A^. polymorphum (Nutt. ! mss.): "leaves deeply pinnatifid or almost 

 entire; segments entire ; petals scarcely longer than the calyx; silique ob- 

 long-linear, compressed ; stigma minute, nearly sessile. 



^- Banks of the Oregon.— (JT) or (a) Stem about a span high. Leaves ra- 

 ther narrow ; the segments short, linear, and acute. Branches from the root, 

 after the developement of the stem and fruit, or shoots from a cropped stem, 

 produce leaves either entire 'or with a few pinnatifid incisions. At other 

 times the whole plant bears similar leaves. FloAvers small." Nutt. 



10. A^. obtusum (Nutt. ! mss.) : "leaves pinnately divided, decurrent; seg- 

 ments irregularly oval, angularly toothed, obtuse ; siliques linear, subterete, 

 twice the length of the pedicels ; style short. 



"Banks of the Mississipsi.— (1) Stem branching above. Racemes lateral 

 and terminal, elongated in fruit." Nutt. 



11. N. Umosum (Nutt.! mss.): "leaves lanceolate, laciniately pinnatifid 

 towards the base, nearly entire above or merely angularly toothed ; laciniae 

 decurrent, subserrate or entire ; pedicels much shorter than the abbreviated 

 siliques ; stigma nearly sessile. 



" Banks of the Mississippi, near New-Orleans.— (2) Subaquatic. Habit of 

 N. palustre. Very smooth. Leaves irregularly but not deeply divided, ex- 

 cept where they approach the water." Nutt. 



12. N. hispidum (DC.) : stem (tall) tomentose-villous ; leaves somewhat 

 villous, runcinate-pinnatifid ; lobes rather obtusely toothed ; siliques (minute) 

 ovate, tumid, pointed with the distinct style, scarcely more than half as 

 long as the somewhat spreading pedicels ; petals scarcely as long as the 

 calyx.— DC. syst. 2. p. 201. Sisymbrium hispidum, Poir. enc. 5. p. 161. 



Near Middfetown, Connecticut, Dr. Barrcdt ! Pennsylvania, Poiret; 

 Middle and Northern States, Nuttall.— 2l 1 Stem 2-3 feet high, much branch- 

 ed above, almost hispidly villous, angular, erect. Leaves 3-6 inches long; 

 lobes numerous, ovate. Racemes numerous, panicled. Flowers minute. 

 Sepals oblong, obtuse. Petals obovate. Silique scarcely more than a line 

 long, exactly ovate, somewhat compressed. Style nearly half the length of 

 the fruit : stigma capitate. Pedicel 2-3 lines long.— A very distinct species, 

 remarkable for its villous stem, and very small ovate siliques. 



13. N. syhestre (R. Brown) : leaves pinnately divided, segments lanceo- 

 late, serrate or incised; petals longer than the calyx; siliques oblong, some- 

 what torulose; style very short. DC. syst. 2. p. 190. Sisymbrium sylvestre, 

 Lin7i. sp. 916. S. vulgare, Pers. syn. 2. p. 196 ; Nutt. gen. 2. p. 68. 



Banks of the Delaware near Philadelphia, NuttalL— Introduced. 



14. A^. cernuum (Nutt! mss.)^ "racemes panicled (flowers white); 

 leaves pinnatifid or laciniate, the segments irregularly and distantly toothed ; 

 silique short, obovate, nodding ; stigma sessile. 



" Ponds of Wappatoo Island at the junction of the Wahlamet Avith the 

 Oregon. — Stem thick and stout. Petals exserted, rather narrow. Pedicels 

 more than twice the length of the fruit. — Allied to N. amphibiurn, but desti- 



