LECT. VI.] THE STEM. ITS DIRECTION. 



249 



lupulus (fig. f, 1), it is termed sinistrorsum ; 



and when it 

 takes the op- 

 posite direc- 

 tion, or from 

 right to left, 

 as in the Scar- 

 let Bean, Pha- 

 seolus multi- 

 Jlorus, the 

 Great Bind- 

 weed, Convol- 

 vulus sepium, 

 or smooth Pe- 

 ri ploca, Peri- 

 ploca Icevigata 



(fig- "/, 2), 

 dextrorsum. 

 The cause of this spiral motion of twining 

 stems I will endeavour to explain, when we in- 

 quire into the movements of plants. 



b. Radicating (radicans), when it sends 

 forth from one side short, fleshy, root-like 

 fibreSj by means of which the plant elevates 

 itself on the perpendicular surfaces of walls 

 and rocks; as in the Ivy, Hedera helix; 

 (fig. g, 1. seep. 250), Ash-leaved Trumpet- 

 flower, Bignonia radicans, &c. In general 



