THE NUTE1TION OF PLANTS. 



161 



(3) Dioncea. This is one of the most famous and re- 

 markable of fly-catching plants (see Fig. 151). It is found 

 only in swamps near Wilmington,, North Carolina. The 

 leaf blade' is constructed like a steel trap, the two halves 

 snapping together, and the marginal bristles interlocking 

 like the teeth of a trap (see Fig. 152). A few sensitive 

 hairs, like feelers, are 

 developed on the leaf 

 surface, and when one 

 of these is touched by 

 a small flying or hover- 

 ing insect, the trap 

 snaps shut and the in- 

 sect is caught. Only 

 after digestion does the 

 trap open again. 



There are certain 

 green plants, not called 

 carnivorous plants, 

 which show the same 

 general habit of sup- 

 plementing their food 

 supply, and so reduc- 

 ing the necessity of 

 food manufacture. 

 The mistletoe is a 

 green plant, growing 

 upon certain trees, from 



which it obtains some food, supplementing that which it 

 is able to manufacture. 



In rich soil, the organized products of the decaying 

 bodies of plants and animals are often absorbed by ordinary 

 green plants, and so a certain amount of ready-made food 

 is obtained. 



FIG. 152. Three leaves of Dioncea, showing 

 the details of the trap in the leaves to right 

 and left, and the central trap in the act of 

 capturing an insect. 



