288 PLANT-LIFE 



are drowned. In some species of Nepenthes the inner 

 margin of the rim is armed with teeth pointing inwards 

 and downwards; these teeth present a barrier impas- 

 sable by any victim which has succeeded in freeing itself 

 so far. The water in the pitcher is at first slightly 

 acidulated by means of a secretion from special glands, 

 but when insects are captured the secretion is greatly 

 stimulated, and a digestive fluid is added. The insects 

 are thus macerated, and their digestible parts enter into 

 the composition of a broth, which seems to be absorbed 

 by special cells situated in the lining of the bottom of 

 the pitcher. 



The Droseracese form a family of carnivorous plants. 

 There are, in the world, six genera and about 110 species ; 

 they grow in sandy or marshy places. In Britain the 

 family is represented by three species, all of the genus 

 Drosera, of which D. rotundifolia, the Round-leaved 

 Sundew, is the commonest and best known. The char- 

 acteristic features of this species are portrayed on 

 Plate LI. The leaves are arranged in a rosette, 

 3 or 4 inches in diameter; they lie pressed to the ground, 

 or with a slight inclination upwards. On their upper 

 surface they are furnished with reddish, knobbed 

 glandular hairs, which may be described as " tentacles." 

 The glands secrete tiny drops of a viscid fluid, which 

 glitter in the sunshine and form an attraction to small 

 insects. Hapless insects that settle on the leaves in 

 hope of securing a sweet morsel are speedily and fatally 

 undeceived. The sticky secretion traps them, and the 

 more they struggle to escape the more inextricable is 

 their position. The glands to which the insect adheres 

 bend inwards with their burden, and in time all the 



