11 



40 THE CRUCIFER FAMILY. 



tj f Leaves all stalked, large and broad 10. Alliaria. 



I Upper leaves sessile or auricled 5. Rockcress. 



fSeeds in two distinct rows in each cell. Pod rather short and curved. 

 8 I 4. Watercress. 



i Seeds blended into one row in each cell. Pod straight, long, or 



^- slender 9 



q J Stem-leaves undivided, narrow at the base 5. Rockcress. 



I Leaves all pinnate or divided 10 



rPod linear. Leaves without bulbs 6. Bittercress. 



10 <j Pod lanceolate-linear. Leaves usually with bulbs in their axils. 



L 7. Toothcress. 



rAll the leaves entire, or toothed only. Plant pale or hoary with 



minute appressed hairs 12 



. Leaves, at least the lower ones, pinnate or lobed at the base. Plant 



v- glabrous, or hairy with rough or spreading hairs 13 



-. o f Pod flattened. Cotyledons accumbent 2. Wallflower. 



I Pod nearly quadrangular. Cotyledons incumbent . . 11. Erysimum. 

 ""Cotyledons accumbent. Pods ending in a style seldom above a line 



long. Plant glabrous, with lyrate or pinnate leaves 14 



Cotyledons incumbent. Yalves of the pod opening to close under the 

 stigma. Plant hairy or glabrous, the leaves deeply pinnate. 



9. Sisymbrium. 

 Cotyledons conduplicate. Pod ending in a beak or conical style, 1 to 

 6 lines long. Leaves irregularly pinnate, or lyrate, or the upper ones 



undivided 12. Brassica. 



f Pods not 6 lines long, on slender spreading pedicels . 4. Watercress. 

 I Pods an inch or more, on stiff short pedicels . ... 3. Wintercress. 



{Pod globular or oblong, or compressed. The valves 

 flat or convex, parallel to the broad partition ... 16 

 Pod compressed or flattened laterally, at right angles to 

 the narrow partition. The valves boat-shaped . . 23 



-. „ J Pod nearly globular or cylindrical 17 



I Pod evidently compressed or flattened 21 



, f. J Minute aquatic plant with subulate leaves 17. Awlwort. 



I Terrestrial plant with flattened leaves 18 



" Flowers white. Cotyledons accumbent 19 



. Flowers yellow 20 



r Plant glabrous. Pod globular or shortly ovoid . . . 13. Cochlearia. 



19 <j Plant hoary or rough with short hairs. Pod somewhat flattened or oblong. 



L 14. Alyssum. 

 'Leaves pinnately lobed, or, if entire, narrowed at the base. (Coty- 

 ledons accumbent.) 4. Watercress. 



20 <j Leaves linear, in dense radical tufts. Flower-stems leafless. 15. Draba. 



| Leaves entire or toothed, the upper ones auricled and clasping the 



stem. (Cotyledons incumbent.) 16. Camelina. 



91 J" Petals deeply divided. (Dwarf annual.) 15. Draba. 



I Petals entire or notched 22 



13 



14 



18{ ] 



