Fig. 42. The telegraph -plaxit (DesTUodium gyrans). Each Leaf is made up of thrt-e 

 leaflets, a large termiual one, and a pair of small lateral ones. In the lowest figure 

 the large leaflets are spread out in their day position ; in the central figure they are 

 turned sharply dovmward in their night position. The name of the plant refers to 

 the peculiar and constant motion of the pair of lateral leaflets, each one of which 

 describes a curve with u, jerking motion, like the second-hand of a watch, as 

 indicated in the uppermost figure. 



