CRUCIFERAE 99 



1. I. pinnatifidus (Michx.) Steud. Pdeplk Rocket. 1°-3° high, 

 glabroas : leaves oblong in outline, dentate : pods Vi"-W long. — In 

 rich woods throughout, but not common. May-July. 



8. RORIFA Scop. 

 Flowers white or yellow. Pods from snbglohose to oblong-linear. 

 Seeds numerous, marginless. Cotyledons aconmbent. The first four 

 species are known as Ykllow Water Cress. 



Flowers yellow. 



Perennial. 1. B. sinuata. 



Annuals. 

 Seeds pitted. 2. E. sesHUflora. 



Seeds minutely tuberculate. 



Pedicels V long. 3. S. oUusa. 



Pedicels 2"-i." long. 4. B. palusiris. 



Flowers white. 

 Creeping and spreading. 5. B. Nasturtium. 



Erect. 6 B. Armoracia. 



1. R. sinuata (Nutt.) A. S. Hitchcock. Branches spreading and as- 

 cending, glabrous : leaves oblong, pinnately cleft : flowers Z"-\" broad : 

 pods i"-6" long. — Quite common in sandy soil along the Missouri 

 River. April-June. 



2. R. sesslliflora (Nutt.) A. S. Hitchcock. Erect, 6'-12' high: 

 leaves oblong, crenate and lobed : flowers 1" broad, nearly sessile : pods 

 oblong, thick — Common with the next. April-November. 



3. R. obtusa (Nutt.) Britton. Much branched and spreading : leaves 

 pinnatifid : flowers 1" broad : pods oblong, V'-b" long. — Common on 

 sand-bars along the Missouri River. April-November. 



4. R. palustiis (L.) Bessey. 6''-2° high, erect, glabrous: leaves 

 oblong, pinnatifid : flowers l'''-2''' broad : pods about equalling the pedi- 

 cels. — Common in wet places throughout. April-November. 



5. R. Nasturtium (L.) Rusby. Watek Ckess. Glabrous : leaves 

 divided into 3-9 oblong to orbicular segments : pedicels about 10" long, 

 widely spreading and as long as the pods. — In springs around Kansas 

 City. Common locally. May-August. 



6. R. Armoracia (L.) A. 8. Hitchcock. Horse Radish. 2°-4° high, 

 from large rootstocks : leaves oblong, crenate to pinnatifid : pedicels 

 ascending : flowers large. — Occasionally escaped along roads. May-July. 



9. CARDAMINE L. BITTER Cress. 

 Pods long, linear, with nerveless valves and seeds in a single row in 

 each cell. Cotyledons acoumbent. 



Plahts not from a tuberous base. 



Terminal leaf segment obovate to orbicular. 



Stems 8' or more high, stout. 1. C. Pennsylvanica. 



Stems 2''-5' high, delicate. 2. C. parviflora. 



Terminal leaf segment linear to linear-oblong. 3. 0. arenieola. 



Plants from a tuberous base. 4. C. bulbosa. 



