286 



PLANT-LIFE 



torious. About 500 species of Carnivorous plants have 

 been distinguislied.. They have been driven to ex- 

 tremities, and compelled by their situation to adopt 

 unusual feeding habits. It may be said of them in 

 general that they exist under conditions where nitrates 

 are commandeered by other plants, or are not present in 

 sufficient quantity for their own health. Nitrogen, we 

 know, is essential to plants. Without it they cannot 

 build up proteins. The Carnivorous 

 Plants have arrangements for the cap- 

 ture and digestion, in one way or 

 another, of animals, from which they 

 extract the nitrogenous materials es- 

 sential to their existence. The usual 

 rule is to capture, say, an insect, then 

 treat it with a digestive fluid, the 

 resultant broth being finally absorbed 

 by osmosis (p. 269) by cells through 

 their cell-walls. 



There are over thirty species of 



Fia. 79. — Pitcher 



OP PlTOHER- 



Plant (Nepbn- Pitcher Plants, found in the tropics, 



mTix,c, DISTILLA- . 



which have assumed the carnivorous 



THES 

 TOEIA), 



habit. We take for description the 

 species Nefenthes distillatoria (Fig. 79). This plant 

 thrives, on marshy ground bordering pools which are 

 to be found in the damp primeval forests of the 

 tropics. In its infancy it seems innocent of designs 

 on the insect fraternity. But the early seed-leaves 

 are succeeded by a rosette of leaves which have a sus- 

 picious look. These leaves rest in part upon the 

 mud, but they curve upwards so that the greater part 

 of their surface is clear of the mud. Each leaf 



