CAENIVOROUS PLANTS 289 



other glands bend in the direction of the captive, as if 

 by common consent, and it is soon held in a sort of 

 octopus grip. Once the glands have secured a firm hold 

 and taken up their intended position, they secrete an 

 acid juice in the first place, and afterwards pump a 

 digestive ferment upon the insect. This ferment dis- 

 solves the nitrogenous matter of the captive, and reduces 

 it to a liquid which can be absorbed by the cells of the 

 leaf. Small flies, such as gnats, are digested in about 

 two days. The indigestible parts of the victim become 

 dry, and as the tentacles are dry for a time after digesting 

 their prey, the wind acts as scavenger, removing the 

 remains. 



The Venus 's Fly-trap (Dioncea muscipula) belongs to 

 the Droseracese; it occurs in peat-bogs in the east of 

 North America, in a strip of country extending from 

 Florida to Long Island. As in Droserd, the leaves form 

 a rosette. Each leaf consists, first, of a flattened petiole 

 which is truncated to the fore, and there contracted to 

 the midrib, and, second, of a rounded blade, the two 

 halves of which are, as it were, hinged. The margins of 

 the blade are fringed with rather long pointed teeth, and 

 on the central area of each half of the surface there are 

 three stiff bristles, which are very irritable. Owing to 

 the irritability of these bristles, an insect coming in 

 contact with them is entrapped by the sudden closing 

 together of the two halves of the blade; they close up 

 like the leaves of a book. When the captive has suc- 

 cumbed it is treated with a digestive ferment, secreted 

 by glandular hairs situated on the surface of the blade, 

 and the liquid product is absorbed and assimilated by 

 the plant. 



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