crucifem:. 



49 



2. Tower Rockcress. Arabis turrita, Linn. (Fig. 50.) 

 (Eng. Bot. t. 178. Towercress.) 



A tall, stiff, erect biennial, approach- 

 ing in size and appearance to the last 

 species, but rough and somewhat hoary 

 with very short forked or stellate hairs. 

 Radical leaves spreading and stalked, 

 stem-leaves oblong-lanceolate, sessile, 

 and clasping the stem by their rounded 

 auricles, all slightly toothed. Flowers 

 small, of a dirty yellowish-white. Pods 

 above 3 inches long, on short, erect pedi- 

 cels, but all curved downwards to one 

 side, forming a long, dense, nodding ra- 

 ceme. Seeds oblong, with a membran- 

 ous border. 



In hedges, on shady banks, and under 

 rocks, in the hilly districts of central 

 and southern Europe, and establishes 

 itself readily on old walls further north, reappearing, truly indige- 

 nous, in the Australian Alps. Indicated at Oxford, at Cambridge, 

 and in Kent, but evidently only introduced into Britain. Fl. spring 

 or early summer. 



Fig. 56 



3. Hairy Rockcress. Arabis hirsuta, Br 



{Turritis hirsuta, Eng. Bot. t. 51.) 



A rather stiff, erect annual or biennial, 

 attaining a foot or rather more in height, 

 but often shorter, usually simple, and 

 rough with short hairs. Radical leaves 

 spreading, obovate or oblong, and 

 slightly toothed ; stem-leaves generally 

 erect, oblong or lanceolate, all, or at 

 least the upper ones, clasping the stem 

 by short auricles. Flowers small and 

 white. Pods slender, 1 to 2 inches long, 

 erect and crowded in a long raceme. 

 Seeds without any wing. 



On walls, banks, and rocks, common 

 in the greater part of Europe and Rus- 

 sian Asia, but not in high northern 

 latitudes. Not an abundant plant in 

 Britain, although occurring in numerous 

 localities even in the north of Scotland. 

 Fl. summer. 



(Fig. 57.) 



