OTHER METHODS OP OBTAINING FOOD 195 



are marsh plants having their leaves arranged in rosettes, 

 which spring apparently from the surface of the soil, and 

 from the centre of which arises a single flower-stalk. Each 

 leaf is modified to form a curious pitcher-like body (fig. 93), 

 furnished with a kind of lid. 

 The pitchers are generally con- 

 spicuously coloured, while the lid, 

 which is the lamina of the leaf, 

 often bears hairs which secrete 

 honey to attract the prey. 



The inner surface of the pitchers 

 is lined with slippery recurved hairs 

 which make it impossible for an 

 insect to climb out of it after once 

 entering. Insects are attracted by 

 the honey, and, venturing upon 

 these hairs, slip down to the bottom 

 of the pitcher, from which escape 

 is impossible. The pitcher contains 

 a quantity of water, due perhaps to 

 the entrance of rain, or possibly 

 secreted to some extent by the 

 surface of the pitcher. The insects 

 become drowned in this liquid and 

 undergo decomposition. Frequently 

 a pitcher will contain so many that 

 the products of their putrefaction 

 are offensive. They are absorbed 

 by the cells of the inner surface. 



Certain other pitcher-plants 

 show a still further advance in their method of obtaining 

 protein supplies. They possess similar means of attracting 

 insects and alluring them to their death, but they do not 

 depend on the slow process of putrefaction for the decom- 

 position of their prey. Instead of this, they secrete and 

 pour out a definite digestive fluid possessing properties like 

 those of the secretions of the stomach and pancreas of 



13* 



FIG. 93. LEAF OF Sarracenia, 



MODIFIED TO FORM A 



PITCHEK. (After Kerner.) 



