(i. CRUCIKERj*:. 23 
** Stiijma a disk or head. 
3. Nastit.tium. Pod terete ; valves convex, veiide.ix. Seeds 
irregularly in 2 rows. 
4. Baebaeea. Pod terete ; ita/ve.t convex, i"it/i (i /jrominenf 
longitudinal rih. Seeds in a single row. 
5. Arabis. Pod compressed ; valves nearly flat, with a pro- 
minent longitudinal rib or with numerous longitudinal 
veins. Seeds in a siwile or double row. 
6. Caedamine. Vod compressed ; valves_ffat, reinless. Seeds 
in 1 row ; seed-stalk simple, filiform. 
7. Dentaeia. Pod lanceolate, compressed ; valves flat, vein- 
less. Seeds in a single row ; seed-stalk dilated, winged. 
Tr. IT. SISYMBEIEJi. Cotyledons incumbent (radicle dor- 
sal), seed compressed. Seeds in one row. 
* Stigma of two dosebj coni'er<iin<j erect ovate lobes. 
8. Hesperis. Pod quadrangular or subcompressed ; valves 
keeled, somewhat 3-veined. Seeds in a single row. 
** Stigma, a disk with a thickened edge. 
9. Sisymbrium. Pod terete or rarely 4-edged ; valves con- 
vex, \vith 3 longitudinal veins. Seeds in a single row, 
smooth : seed-stalk filiform. — -S'. Thalianum has a tetra- 
gonous pod with 1 strong conspicuous rib on the valves. 
10. Alliaeia. Pod terete ; valves convex, with 3 longitu- 
dinal veins, the middle one prominent and strong, the 2 
lateral slender and branching. Seeds in a single row, 
striate ; ^eed-stalk flatteiwd, ivinged. 
11. Erysimum. Pod 4-edged ; valces prominently keeled, 
ivith 1 longitudinal vein. Seeds in a single rov.* ; seed-stalk 
filiform. 
Tr. III. BRASSICEjE. Cotyledons conduplicate (longitudi- 
nally folded in the middle) ; radicle dorsal, within the fold. 
12. Brassica. Cal. erect. Pod terete or angular. Seeds 
globose, in a single row. 
13. Sinapis. Cal. spreading (in the flower). Pod terete or 
angular. Seeds in a single row. 
