CRUCIFER^ 51 



2. C. sempgrvirens, (L.) Pers. 



Strict, erect, 6-24. in. high; corolla pink tipped with yellow, spur short; 

 flowers in panicled racemes. Rocky places, N. Man.-Alta., not common. 



XXXIII. CRUCfFERffi (Mustard Family). 



Herbs with a pungent juice, alternate leaves and cross-shaped 

 corollas; sepals 4, deciduous; petals 4, hypogenous, arranged in 

 form of a cross; stamens 6, in two groups, 4 long and 2 short; pod 

 usually of two ceUs separated by a thin partition, and bearing several 

 to many seeds. A large family containing some of our most trouble- 

 some weeds. 



1. DRAB A. 



Pods oval or oblong, flattened;' seeds in two rows in each cell. 

 Low herbs with leaves either toothed or entire, and with white or 

 yellow flowers. 



1. D. nemerdsa, L. 



Leaves somewhat lanceolate and more or less toothed; pods oblong on 

 spreading pedicels which are about twice the length of the pods. Sandy 

 soil, Man.-Alta. 



2. ERYSIMUM. Treacle Mustard. 



Pods linear, generally 4-sided, valves strongly keeled; stigma 

 lobed; seeds oblong, in 1 row in each cell. Erect annual or biennial 

 herbs more or less pubescent, often rough, with simple leaves, entire 

 or not deeply lobed. 



1. E. cheiranthoides, L. Wobm-seed Mustard. 



Stem slender, erect, branching, 6 in.-2 ft. high, rough; leaves lanceolate, 

 entire or slightly toothed, the lower short-petioled, the upper sessile but 

 not clasping; flowers small, yellow; pods short, obtusely 4-angled, spreading 

 on short pedicels. Moist ground and waste places, Man.-Alta. 



2. E. asperum, DC. Western Wall-flower. Prairie Rocket. 



Stout, erect, 1-2 ft. high, simple or branching, rough; upper leaves sessile, 

 usually entire^lower leaves petioled, lanceolate or linear, and entire or deii- 

 tate ; flowers large, yellow, showy ; pods long, linear, rough, spreading on 

 short pedicels. Dry sandy prairie, Man.-Alta. 



3. E. parviflSrum, Nutt. 



Stem erect, simple or sparingly branched, roughish, 1-2 ft. tall; leaves 

 oblanceolate to linear, the upper sessile, the lower on Slender petioles ; 

 flowers small; pods narrow, ascending on short pedicels. Touchwood Hills, 

 Hand Hills, Cypress Hills, and similar localities: 



