CRUCIFERAE (MUSTARD FAMILY) 



73 



CARDAMINE 



Herbs with fibrous roots, sometimes tuber-bearing. Stems leafy, 

 with alternate, simple or compound leaves, and bearing a cluster of 

 white or purple flowers and linear flat pods. 



C. bulbosa, Spring Cress. Stem smooth, from 

 a tuberous base and a slender rootstock bearing 

 small tubers; root-leaves oblong to heart-shaped, 

 stem-leaves 5-8, scattered, becoming narrower 

 above, often toothed; flowers white. In wet 

 meadows and around springs. May, June. 



C. Douglasii, Spring Cress. Like the last, but 

 stem usually pubescent, root-leaves orbicular, and 

 flowers rose-purple. Rich woods. April, May. 



C. pennsylvanica, Pennsylvania Bitter Cress. 

 Stem from fibrous roots, usually smooth, and 

 bearing pinnate leaves with 7-11 leaflets; terminal 

 leaflet obovate, lateral ones oblong; flowers small, 

 white. Moist places. 



ARABIS 



Cardamine Douglasii, 

 Spring cress. 



Stem from fibrous roots, with no tubers, bear- 

 ing alternate simple or pinnatifid leaves, a cluster of white or 

 purple flowers, and linear flat pods. 



A. lyrata, Rock Cress. Branching 

 from the base, smooth except the lyrate- 

 pinnatifid root-leaves; stem leaves scat- 

 tered, narrow, with tapering base, toothed 

 or entire; flowers white, the petals much 

 longer than the sepals. On rocks or 

 sandy places. April to July. 



A, laevigata. Smooth Rock Cress. 

 Stems simple and very leafy, with root- 

 leaves rarely lyrate, and narrow stem 

 leaves, mostly toothed and partly clasp- 

 ing by an arrow-shaped base; flowers 

 white and small, the petals scarcely 

 longer than the sepals. Rocky places. 

 Arabis lyrata, Eock cress. May. 



