Natural History 613 



to fold inwards. The stimulus spreads, and the struggling midge 

 is pinned down in the centre of the leaf. Secretion of fluid in- 

 creases, and in it the insect is first drowned and then digested. 

 Some days after the fatality the tentacles bend back once more, 

 uncovering a shrivelled husk. The leaf is ready for fresh prey. 

 The butterwort, like the sundew, traps its prey by a viscid 

 secretion; it possesses no tentacles, but the margins of the boat- 

 shaped leaves, covered with tiny glands which secrete the sticky 

 matter, roll inwards. Digestion is slower than with the sundew, 

 but ultimately the softer parts of the insect are absorbed and only 

 the husk is left. The bladderwort adopts other means. It grows 

 submerged in pools of peaty water, and, as is the case in many 

 water-plants, its leaves are divided into fine threads. Some of 

 these are replaced by bladders about one-tenth of an inch long. 

 The bladder opens in front by an arrangement like the door of an 

 old-fashioned mouse-trap. Small freshwater crustaceans get 

 entangled in a tuft of hairs projecting over the door, and force 

 their way in. The door of the trap falls to behind them and cannot 

 be opened from the inside; they swim round and round till they 

 die, and then under the action of the bacteria of decay their bodies 

 rot and are absorbed. 



Pitcher Plants 



Curious as are the British carnivorous plants we have just 

 described, they are excelled, alike in numbers and in refinement, 

 by those of the Tropics. Visitors to the glass houses of the 

 Botanic Gardens at Kew or Edinburgh are familiar with the 

 pitcher plants, Nepenthes and Sarracenia. Most of the Nepenthes 

 are natives of the Malay region, where they ramble and climb 

 through the bush. They have large leathery leaves prolonged into 

 whiplike tendrils. The end of the tendril, after it has grasped its 

 support, develops into the pitcher, which in some species is as large 

 as a quart pot, in others as small as a thimble. Over the mouth 

 arches a lid which prevents the entrance of rain, for the liquid with 



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