192 



PRACTICAL COURSE IN BOTANY 



impossible to a small insect when once it is ensnared. 

 When we remember that these plants are generally found 

 in poor, barren soil, we can appre- 

 ciate the value to them of the ani- 

 mal diet thus obtained. 



210. Flytraps. — The most re- 

 markable examples of insect-catch 

 ing leaves are the Venus 's-fly trap, 

 found in the seacoast region of 

 North Carolina, and the sundew 

 {Drosera rotundifolia) , common on 

 the margins of sandy bogs and 

 ponds. The latter is a delicate, 

 innocent-looking little plant, and 

 owes its poetic name to the dewlike 

 appearance of a shining, sticky 

 fluid exuded from glands on its 

 leaves, which glitter in the sun like dewdrops. It is, however, 

 a most voracious carnivorous plant, the sticky leaves acting 

 as so many bits of fly paper by means of which it catches its 



Fig. 260. — Plant of sundew. 





263 



Figs. 261-263. — Leaves of sundew magnified : 261, leaf expanded ; 262, leaf 

 closing over captured insect ; 263, leaf digesting a meal. 



prey. When a fly has been trapped, the tentacles close 

 upon it, the edges of the leaf curve inward, making a sort of 

 stomach, from the glands of which an acid juice exudes and 



