36 UKDEK 11. CRUCIFER^E. 



1. NASTURTIUM, R. Br. WATER-CRESS. (Lat. nams tortus, now 

 tortured ; alluding to the pungent qualities.) Sep. spreading. Siliques 

 subtcrete, turgid, generally curved upward, often shortened to a silicic, 

 valves veinless. Seeds small, oo, turgid, generally arranged in a double 

 row in each cell (=o). ? with pinnate or pinnatifid leaves. 



* Petals white. Siliques rather long (1012") No. 1 



* Petals yellow, minute. Siliques shortened (4 S"), but longer than the pedicels, (a) 



* Petals yellow. Siliques or silicles (1 6"), shorter than the pedicels. (b) 



a Leaves pinnate or pinnatifid. Diffusely branched Nos. 2, 3 



rt Leaves lyrate, or merely toothed. Stems erect Nos. 4, 5 



b Petals not longer than the calyx, obscure Nos. 6, 7 



b Petals longer than the calyx, bright yeLow, the flowers showy Nos. 8, 9 



1 N. offlolnAlc R. Br. English W. Lvs. pinnate, Ifts. ovate, subcordate, repand ; 



finis white, longer than the calyx. 11 Springs, <fec. May, June. J 



2 JV. tanacetffollum Hook. Upper leaf-segm. confluent, lower distinct, oblong, or 



roundish, sinuate-toothed, teeth obtuse; pods 4 fy', ped. J as long. (2) South. 



p. vbtunum. Lfts. mostly distinct, obtuse, oval. Pods shorter (3 5"). Miss. R. 

 'A N. Walter! Wood. Segments of the leaves all distinct, narrow, with a few linear, 

 acute lobes or teeth ; pods linear (5"), ped. 2 3". 11 South. 3 5'. March, April. 



4 N. Ilmosum N. Lvs. lanceolate, toothed, the lower lyrate ; pods elliptic-oblong, 



3 4", ped. much shorter. @ Rivers, La. 10 \y. Fls. minute. Too near the next. 



5 N. sessIHflorum N. Lvs. wedge-obovate, repandly-toothed or subentire; pods 



linear-oblong, 5 6", subsessile. @ Miss. Riv. Stem erect. Fls. minute. Apr. June. 



6 N. pal it st re DC. Marsh Cress. Glabrous; Ivs. pinnately lobed, amplexicaul, lobes 



confluent, dentate ; rt. fusiform ; pet. as long as the sepals ; silicic spreading, turgid, 

 twice longer than wide. y. Wet places. 1 2f. Pod 3". June Aug. 



7 N. liispidum DC. Villous : Ivs. rnncinate-pinnatifid, lobes obtusely dentate ; sili- 



cles tumid, ovoid, or globular, the pedicels longer, ascending ; pet. scarcely as long as 

 the calyx. Streams, 1 3f. Pod 1". Ped. 23". June Aug. 



8 N. syl vestre R. Br. Wood Cress. Lvs. pinuately divided, eegm. serrate or incised ; 



pods linear, style very short, it Meadows, Ms. to Pa. Rare. June, July. 



9 N. simiat 11 111 Nutt. Lvs. pinnatifid, segm. lance-oblong, nearly entire ; podg 



oblong, acute, with a slender style, li Rivers, St. Louis to Oreg. June. 



2. TURRITIS, Dill. TOWER MUSTARD. (Lat. turns, a tower; from 

 the strict form of the plants.) Sep. erect, converging. Seeds flattened, 

 minute, in 2 rows in each cell of the long, narrowly-linear 2-edged silique ; 

 valves plane, 1-veined. Embryo = o . Glabrous and strictly erect, stem- 

 leaves sagittate-clasping. (Runs into Arabis.) 



1 T. gl&bra L. Fls cream-white, erect ; silique long (30, strictly erect ; stem IVB. 



ovate-lanceolate. (T) Can., to Pa. (Porter.) 2 3f. Glaucous. Lvs. entire. July. 



2 T. stricta Graham. Fls. rose-white, erect; silique long (30, erect, finally ascending 



or spreading ; stem Ivs. linear-lanceolate. @ Rocks, N. Y. (rare) to Oreg. 1 2f. May 

 p. braeliycdrpa. Fls. and siliques spreading, the latter shorter (10- Westward. 



3. IODANTHUS, T. & G. FALSE ROCKET. (InSr??, violet-colored, 

 a rSo?, flower.) Calyx closed, shorter than the claws of the petals. Si- 

 lique linear, terete, veinless. Seeds arranged in a single row in each ceL 

 (=o). If Glabrous, with violet-purple flowers in panicled racemes 

 Leaves lanceolate. 



I. hesperloides Torr & Gr. Penn. to Dl. and Ark. 2 3f. Lvs. serrate or the Iowa 

 pinnatifid-lyrate. Pods 1520", spreading. May, June. (Arabis, Gr.) 



