THE PLANT IN ACTION. 



261 



If, now, it be touched by the hand, or the warm 

 breath, the whole leaf is quickly affected, and col- 

 lapses. First, the leaflets close in pairs, bringing 

 their upper faces together, and, inclining forward, 

 then the four outspread leaves approach each other, 

 and, at the same time, the main leaf-stalk turns 

 downward, so that the leaf presents the appearance 

 shown in Fig. 416. 



Another remarkable instance of sensitiveness in 

 a plant occurs in a case of the Venus's-Flytrap of 

 North Carolina, represented in Fig. 417. It is the 



FIG. 417. 



leaf that plays the part of the trap, both in its struct- 

 ure and in its action. The midrib of each leaf plays 

 the part of a hinge, while its upper surface is covered 

 with fine bristles, and its margin is sharply toothed. 



