NATURAL HISTORY STUDIES 



Its habits, too, how adaptive they are ! the quick 

 hunting close to the surface, the slow deep burrowing 

 below the reach of the frost's fingers in winter, the 

 nest-making below the chief mole-hill or fortress, 

 the making of a special tunnel to the nearest water, 

 and so on. Dr. Bitzema-Bos has verified the 

 observation that moles make a store of earthworms 

 for the winter months, biting their heads off so that 

 they lie inert but not dead. If this were done in 

 the summer months the head would be regrown 

 and the captives would crawl away, but below a 

 certain temperature the regrowth does not occur, 

 and the decapitated earthworms lie imprisoned 

 without walls. 



Fly Trap 



As a fine example let us take Venus 's Fly Trap 

 (Dioncea muscipula), a member of the Sundew 

 family, in which there are many adaptations to 

 catching and digesting insects. The trap of Dionsea 

 is a much modified leaf, or part of a leaf. The blade 

 consists of two nearly semicircular halves, united 

 by a strong midrib ; the surface is studded with 

 reddish glands, and bears on each side three sensitive 

 jointed hairs ; on each margin there are about 

 twenty spikes directed upwards and inwards ; 

 the stalk of the leaf is like the handle of a teaspoon 

 with a channelled upper surface and a narrow 

 isthmus where it joins the blade. 



When an insect, attracted to the glistening 

 moist surface, touches one of the upstanding jointed 

 hairs, the halves of the blade begin at once to close 



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