Oeder 13.— the CRUCIFERS. 16' 



1 A. Ludovicia'na. LonUiana R. All the leaves feather-cleft. Seeda bor- 



dered. Plant slender, 6-10' high. S. i/ar., Afr. 



2 A. lyra'ta. Lyre-leaved R. Only the root leaves feuther-cleft. Seeds nol 



bordered. Plant 6-12^ high. Pods li-2Mong. 

 8 A. Thalia''na. Mouse-ear R. Steins erect. Leaves nearly entire. Petals twice 



longer than the sepals. Pods erect. Plant dcwny. May. 

 4 A. denta^ta. Toothed R. Stems diifuse. Leaves sharply toothed. Petals scarce 



longer thif. sepals. Pods spreading. Eough. M. W. 



5 A. patens. Patent R. Downy. Pods spreading and curved upwards, beaked 



with a distinct style, w. W. S. 



6 A. hirsu'ta. Hairy R. Plant hairy. Siliques straight, erect. Style none. 



Leaves arrow-shaped. Fls. g. 



7 A. laeviga^ta. Smooth Sickle-pod. Stem leaves arrow-shaped, clasping, narrow. 



Pod spreading. Plant glabrous, 2f. high. 



8 A. Canaden'sis. True Sickle-'pod. Stem leaves pointed at both ends, sessile. Pod 



curved, pendulous. Tall, downy. 



8. DENTA'RIA. Tooth-root. Pepper-root. 



ISepals converging or closed. Silique lanceolate, with flat, veinless 

 valves opening elastically. Seeds in a single row in each cell, ovate, not 

 bordered. — Plants %. Rhizoma prostrate, jointed. Stem leaves but 2 or 

 3. Elowers white or purplish. 



T[ Stem leaves almost opposite or whorled. . . 1, 2, 3 



H Stem leaves alternate or scattered. Koot-stock moniliform 4, 5 



1 D. diphyl'la. Two-leaved P. Stem leaves 2 only, leaflets 3, ovate, toothed. 



2 D. lacinia'ta. Gut-leaved P. Stem leaves 3, leaflets 3-5, linear, cleft. 



3 D. multif'ida. Stem leaves 2-3, numerously divided into linear leaflets. S. 



4 D, max'una. Leaflets 8, ovate, cut and cleft. Lvs. 3-7. Fls. purple. M. 



5 D. heterophyl'la. Lflts. 3, nearly entire ; of the rt. lvs. round-ovate, toothed. 



9. OARDAMI'NE. Bitter Cress. 

 Calyx a little spreading. Silique linear, with flat, veinless valves whicli 

 are narrower than the partition. Stigma entire. Seeds not margined, 

 with a slender seed-stalk. Flowers white or purple. 



* Leaves pinnate with many leaflets. April- June 1,2 



* Leaves simple or partly ternate. Mojstly perennials. ...a 



a Style slender. In low, wet grounds 



a Stylo none. In high mountains 



1 C. hirsu'ta. Pennsylvanian G. Smooth, about If. erect. Leaves 5-11-foliatc, tli 



terminal lobe largest, 3-lobed. Stigma sessile. Wet. (3) c. 



2 C. praten^sis. Guckoo-Jknver. Stem simple, ascending. If. Leaves 7-15-foliate, 



with stalked, roundish leaflet* Style present. Flowers large. Wet. U 



