106 



ELEMENTS OP BOTANY. 



In the Venus' flytrap, which grows in the sandy regions of 

 eastern North Carolina, the mechanism for catching insects is 

 still more remarkable. The leaves, as shown in Fig. 96, 

 terminate in a hinged portion which is surrounded by a 

 fringe of stiff bristles. On the inside of each half of the 

 trap grow three short hairs. The trap is so sensitive that 



when these hairs are touched 

 it closes with a jerk and very 

 generally succeeds in captur- 

 ing the fly or other insect 

 which has sprung it. The 

 imprisoned insect then dies 

 and is digested, somewhat as 

 in the case of those caught by 

 the sundew, after which the 

 trap reopens and is ready for 

 fresh captures. 



131. Object of Catching 

 Anirrml Food. — It is easy to 

 understand why a good many 

 kinds of plants have taken to 

 catching insects, or even (in 

 the case of some of the large 

 tropical pitcher plants) to 

 catching birds, killing them, 

 digesting them, and absorbing 

 the digested products. Car- 

 nivorous, or flesh-eating, 

 plants belong usually to one of two classes as regards their 

 place of growth : they are bog-plants or air-plants. In either 

 case their roots find it difficult to secure much nitrogen- 

 containing food, that is, much food out of which proteid 

 material can be built up. Animal food, being itself largely 

 proteid, is admirably adapted to nourish the growing parts of 



Fig. 95. — Venus' Flytrap. 



