160 



XIII. CRUCIFERiE 



FIG. 40.— 1. A flower of Sinapis nigra. 2. The stamens (4 long and 2 short) and pistil. 3. Plan of the 

 flower,— stamens in 2 rows, outer row half wanting. 4. A silique,— 5, partly open, showing the septum 

 with seeds attached. e.Cross section ofa seed, cotyledons conduplicate (0>>). 7. Flower (enlarged) and leaf 

 of Capsella. 8. A si!icle,—9, open, showing the narrow septum with seeds. 10. Cross section of a seed, 

 cotyledons incumbent (0 II). 11. Section ofa winged seed of Arabia Canadensis, cotyledons accumbent o li. 



Conspectus of the Genera. 



* Ornamental exotics not culinary.' 



( Silicle 5 Some of the stamens toothed. 

 < 2-celled . ( Stamens all toothless 

 < Petals equal. ( Silicle icelled, l-seeded. 

 Fruit siliculose ; { Petals unequal, the 2 outer ones larger. 

 S Stigma capitate. 

 5 Seeds flat(0= ). J Stigmas comute. 

 Fruit siliquose ; ^ Seeds ovoid <on). Caly.x furrowed at base. . 



Alyssum.. 8 

 Lunaria. 9 



Isalis. 1 1 



Iberis. 1 



CheArantkus. 21 



Malthiola. 

 Hesperis. 



** Plants native or naturalized, and culinary exotics. 



< 4— oo-seeded. 

 ("ovate and < emarginate, J 2-seeded. 

 I compressed, ( entire at the apex. 

 < ovoid or 4 Leaves cauline. 

 globose. ( Leaves radical. 



( Silicle 

 f Fruit <jointless, L triangular, cuneate at base 

 ■' culose. ( 



Flowers 



Silicle with 2 joints, upper joint ovate or ensiform. 

 ( Sds. not 



("Valves 

 J veinlesa. 



("Seeds in a 

 1 single row. 

 I Seeds in a 

 . I double row. 



Fruit ] Valves with one central vein, flat, linear 



bordered, ^O'l. 

 4 Pods linear. ( Seeds bordered. 

 I Pods lanceolate. Leaves few 



i wingless 



winged on the margin. . 



25 



Thlaspi. 

 Lepidium. 

 Draba. 

 Cochlearia. 

 Subularia. 

 Capsella. 

 Cakile. 

 Cardamine. 

 msymbrium. 19 

 ChRiranthus. 21 

 Dentaria. 17 

 Nasturtium. 12 

 Turritis. 14 



Arabis. T5 



Raphanus. 26 

 Brassica. 24 



Raphanvs. 26 

 Barbarea. 13 

 Erysimum,. 



I'iuwcia r I uiL vaivca \\iLllu[it:i 



cyanic. L siliquose. I Valves 0. Silique indehiscent, transversely celled 



\ Pods dehiscent. 

 ( globose. < Pods indehi.^cent. 

 ( Seeds in a < oblong (0=). Leaves lyrate. 

 ("Calyx erect < single row, ( oblong (on ). Leaves undivided 



J or closed. ( Seeds in a double row I'llrritis. 14 



("Fruit ] i .Seeds ovoid or oblong (0(1). . . Sisymbrium. 19 



I siliquose. I Calyx spreading. • . ^ Seeds globose (0>>). . . . Sinapis. 23 



Flowers I ^ oblong or somewhat terete NasHirtinm. 12 



yellow. L Fruit siliculose, . . J obovoid or subglobose Camelina. 7 



Section I. SILICULOSE. {{\ 80, note.) 



1. THLASPI. Dill. 



Gr, ^\aw, to compress ; on account of the compressed or flattened silicles. 



Calyx equal at base ; petals equal ; silicle short, flat, emarginate 

 at the apex, many-seeded ; valves carinate, often winged on the 

 back ; cotyledons accumbent (0 = ). — Lvs. undivided. Fls. white. 



1. T. arven.se. Penny Cress. 



Iais. oblong, coarsely dentate, smooth; silicle roundish-obovate, shorter than 

 the pedicel ; stig. subsessile. — In cultivated, stony fields, Can. and Northern States. 

 The whole plant smooth, 8 — 12' high, branched. Leaves 1 — 2' long, J as wide, 

 the cauline slightly arrow-shaped with .small obtuse auricles, wavy and toothed 



