50 



THE CRUCIFER FAMILY. 



Fringed Rockcress. Arabis ciliata, Br. (Fig. 58.) 



(Turritis alpina, Eng. Bot. t. 1746.) 



Very near the hairy H., but not above 

 6 inches high ; the stem usually glabrous, 

 and the leaves only fringed with a few 

 stiff hairs on their edge, the upper ones 

 rounded at the base and not auricled. 

 The flowers are rather larger, and the 

 pods less erect. 



In stony and rocky places, in the 

 mountains of central Europe. In Britain, 

 only by the seaside at Rinville, Cunne- 

 mara, in Ireland. Fl. summer. There 

 is some doubt whether the Irish and 

 the Continental plants are the same ; but probably both are mere va- 

 rieties of the common hairy R. 



Fig. 58. 



5. Thale Hockeress. Arabis Thaliana, Linn. (Fig. 59.) 

 (Eng. Bot. t. 901. Sisymbrium, Brit. Fl. Thalecress. Wallcress.) 



A slender, erect, branching annual, 

 usually about 6 inches high, but some- 

 times attaining a foot, clothed with short, 

 spreading, stiff hairs, or sometimes nearly 

 glabrous. Leaves mostly radical and 

 spreading, oblong, with a few coarse 

 teeth from | to 1 inch long. Stem-leaves 

 few, small, and sessile. Flowers small 

 and white. Pods on spreading pedicels, 

 in slender racemes, narrow linear, vary- 

 ing from 4 or 5 lines long to twice that 

 length. Seeds small, the two rows blended into one ; the cotyledons 

 placed obliquely, so that the radicle is almost incumbent on the back 

 of one of them. 



On old walls, dry banks, and stony waste places throughout Europe 

 and Russian Asia, extending into northern America. Frequent in 

 Britain. Fl. early spring, and occasionally also in summer and autumn. 

 On account of the position of the radicle, this species is referred by 

 some to Sisymbrium, with which it has little else in common. 



Fig. 59. 



6. Bristol Rockcress. Arabis stricta, Huds. (Fig. 60.) 

 (Eng. Bot. t. 614.) 

 A perennial, but probably of few years' duration, resembling in some 



