196 
C 4 Plants glabrous, often glaucous 
8 Leaves rotund-cordate ll. Cardamine 
@ Leaves oblanceolate or oval, tending to obovate, 
/Z, those on the stems sessile and clasping 
12, Arabis 
/O Flowers purple 
/O Flowers white 
i2 Flowers rather distant upon rachis, not densely 
/6 crowded 64 Thlaspi 
| Flowers close-set, in rather densely crowded 
'» clusters s. Lepidium 
(> Plants more or less pubescent with simple or branched hairs 
& Hairs simple, rarely forked (see also Draba) 
/O Perennial herbs withstems arising from a branching 
/A- caudex, the basal leaves tufted 12. Arabis 
w) /® Slender annuals, the leaves not tufted 2 Thysanocarpus 
4 Hairs branched 
{O Plants 30-60 cm, tall or more 12. Arabis 
i’ 
‘9 Plants 10-30 cm, tall, rarely more 
ee eee 
i722, Slender annuals with slender stems 
‘4 Pedicels recurving after flowering 3q Athysanus 
‘“, Pedicels remaining ascendent 9. Draba 
i. Low perennials with a woody caudex 
“i 
/4 Leaves 5-10 mm, long 9, Draba 
12, Arabis 
/4 Leaves 10-350 mm, long 
| 3bhLeaves distinctly pimatifid to pinnately compound 
Low perennials, the leaves canescent, tufted upon the close-set 
so root crovm 44. Smelowskia 
( Annuals or leafy perennials 
q Jo Plants aquatic or amphibious; stems leafy well into the 
/*+ inflorescence /6 Radicula 
Plants of dry fielas and waste places; stems leafy below, 
2c or bracteate 
