1 1 2 Brassicaceae 



or corymbose white, yellow, or pink flowers; 

 sepals and petals 4; stamens 6, rarely fewer; 

 pistil i, consisting of 2 united carpels. 



Pods short; silicles. 



Pod compressed parallel to the partition. Draba. 



Pod compressed contrary to the partition, ovate ; 



flowers white. Thlaspi. 



Pod inflated, obcordate; flowers yellow. Physaria. 



Pods elongated; siliques. 



Pod compressed parallel to the partition. 



Valves nerveless; flowers white. Cardamine. 



Valves i -nerved; flowers white or pink. Arabis. 

 Pods terete, not at all compressed. 

 Pods i inches long or more. 



Flowers yellow, stigma 2-lobed. Erysimum. 



Pods less than i J inches long. 



Leaves grey with fine hairs; flowers white. 



Smelowskia. 



Leaves not grey-hairy ; flowers yellow or white. 

 Pubescence of simple hairs. Sisymbrium. 



Pubescence of forked hairs. 



Leaves pinnate or pinnatifid ; flowers yellow. 



Sophia. 

 Leaves entire or nearly so; flowers white. 



Braya. 

 Smooth throughout. 



Leaves pinnate or pinnatifid ; flowers white. 



Roripa. 



Draba Caudex much branched, branches 



glacialis short and slender. Leaves 



Adams strongly keeled, J-f of an inch 



long, more or less loosely stellate-pubescent, 



