90 ELEMENTS OF BOTANY. 



larly lyrate-pinnatifid, the lower petioled, the upper sessile ; flowers 

 small ; petals yellow ; pods linear, spreading, longer than the pedi- 

 cels. March- April. In wet places. 



III. CARDAMINE. 



Annual or perennial 5 rootstock often scaly or bulbiferous ; 

 stem erect or ascending, usually glabrous ; leaves more or 

 less divided; flowers in terminal racemes, white or purple; 

 petals rather large ; stamens 6 ; fruit an elongated silique, 

 seeds several in a single row in each cell. 



C. BULBOSA (Schreb.) B. S. P. Bulbous Cress. Perennial; 

 root tuberous; stem simple, erect, smooth, without runners, 9-18 

 in. tall ; lower leaves long-petioled, ovate, orbicular or cordate, often 

 angled or toothed, the upper short-petioled or sessile, lanceolate or 

 oblong, toothed or entire ; pedicels i-I in. long ; petals white, ^-i 

 in. long ; silique erect, linear-lanceolate, tipped by the persistent 

 style ; seeds round-oval. April-May. Cool, wet places. 



C. HiRSUTA L. Hairy Bittercress. Annual ; stem slender, 

 erect, simple or with a few slender branches, more or less pubescent, 

 6-15 in. tall ; leaves mostly in a cluster at the base of the stem, 

 pinnately divided, the terminal lobe orbicular, the lateral lobes nar- 

 rower, somewhat hirsute above, stem leaves nearly linear ; flowers 

 small ; petals white, longer than the sepals ; stamens 4; pods linear, 

 erect on erect pedicels, about 1 in. long ; seeds oval. March- April. 

 In waste places. 



IV. BURSA. 



Annual ; stem erect ; pubescence of branched hairs ; racemes 

 terminal, becoming elongated in fruit ; flowers small, Avhite ; 

 silicle obcordate or triangular, flattened contrary to the 

 partition, shorter than the spreading pedicel. 



B. Bursa-pastoris (L.) Britt. Shepherd's Purse. Root long 

 and straight ; stem branching above, pubescent below, smooth 

 above ; lower leaves forming a rosette at the base of the stem, irreg- 

 ularly lobed or pinnatifid, stem leaves lanceolate, clasping, toothed 

 or entire ; sepals pubescent, about half as long as the petals ; pod 

 triangular, emarginate or cordate at the apex ; seeds several in each 

 cell. February-July. A connnon weed. 



