Insectivorous PIa?ifs 



283 



Insectivorous plants — The plants that capture insects 

 and other animals for food are a few bog plants such as 

 sundew and pitcher-plant, and a number of submerged 

 bladderworts. These 

 have turned tables on 

 the animal world. Liv- 

 ing where nitrogenous 

 plant-foods of the or- 

 dinary sorts are scanty, 

 they have evolved ways 

 of availing themselves 

 of the rich stores of pro- 

 teins found in the bodies 

 of animals. The sun- 

 dew seems to digest its 

 prey hke a carnivore; 

 the bladdenvort ab- 

 sorbs the dissolved sub- 

 stance like a scavenger. 

 Charles Darwin studied 

 these plants fifty years 

 ago, and his account 

 ('75) is still the best 

 we have. 



The sundew, Dro- 

 sera, captures insects 

 by means of an adhesive 

 secretion from the tips 

 of large glandular hairs 

 that cover the upper surface of its leaves (fig. 172). 

 The leaves are few in number and spatulate in form, and 

 are laid down in a rosette about the base of a stem, 

 flat upon the mud or upon the bed of mosses in the 

 midst of which Drosera usually grows. They are red 

 in color, and crowned and fringed with these purple 



Fig. 172. A leaf of sundew with a 

 captured caddis-fl}'. The glandular 

 hairs are bent downward, their tips 

 in contact with the body of the 

 insect. Other erect hairs show 

 globules of secretion enveloping their 

 tips. 



