CARNIVOROUS PLANTS 



353 



to make out this strange folding of the leaf by an examination of the 

 exterior only, but a longitudinal section, made with a sharp knife 

 or razor, will show it clearly. 



When minute animals enter the cavity of the leaf through the 

 little openings above mentioned, they are seized by means of small 

 filaments that protrude from the lining cells ; and although no 

 special digestive secretion has been 

 discovered in the leaves, it appears 

 certain that the creatures en- 

 trapped are really dissolved, for 

 nothing remains of them after a 

 time except the harder, indigestible 

 portions. Also, there is every 

 reason to believe that the products 

 of digestion are absorbed, probably 

 by the same filaments that are 

 concerned in the capture of the 

 microscopic prey. 



Perhaps the most interesting of 

 the carnivorous plants are those 

 which exhibit distinct movements 

 in connexion with the capture of 

 then- prey, and among these are 

 the British Butterworts and Sun- 

 dews, which grow in bogs and 

 other wet places. 



There are tliree British species 

 of Butterwort {Pinguicida), similar 

 in structure and habit, all growing 

 in bogs and on wet rocks. They 

 have each a rosette of entire, 



radical leaves, the lowest of which lie close against the soil or 

 rock on which the plant grows ; and violet or yellow flowers on 

 leafless peduncles. The calyx has four or five teeth, arranged in 

 two lips ; and the corolla, which is also lipped, has a broad, open 

 throat, and a spur. 



The commonest species is the Common Butterwort (P. vulgaris), 

 which is found in bogs and wet places, principally in the hilly, humid 

 districts of the West of Britain and Ireland, flo\^ering from May to 

 July. Its leaves are succulent and clammy, of a pale green colour, 

 and covered all over with little glistening spots. The flower stems 



AA 



COMMON Butterwort. 



