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THE PHILOSOPHY 



Another fpecies of caterpillar conftruds Its cod In the form of a 

 boat with the keel uppermoft j but It confifts not entirely of pure 

 filk. The animal, with its teeth, detaches fmall triangular pieces of 

 bark from a bufh or a tree. Thefe pieces of bkrk it paftes upon Its 

 body by means of a glutinous or filky fubftance, and they conftitute 

 a principal part of its cod. 



Another fpecies works alfo in wood, though not with equal art as 

 the former. Its cod is compofed entirely of fmall irregular frag- 

 ments of dried wood. Thefe fragments the animal has the addrefs 

 to unite together, and to form of them a kind of box which covers 

 and defends its whole body. It accompliflies this purpofe by molften- 

 ing, for fome moments, the pieces of wood in its mouth, and then 

 attaches them to each other by a glutinous fubftance. Of this mix- 

 ture the caterpillar forms a cod, the folidity of which is nearly equal 

 to that of wood. 



The moft folltary of all Infeds are thofe who live in the internal 

 parts of fruits. Many of them undergo their metamorphofis in the 

 fruit Itfelf, which affords them both nourifhment and a fafe retreat. 

 They dig cavities in the fruit, which fome of them either line with 

 filk, or fpin cods. Others leave the fruit, and retire to be transform- 

 ed in the earth. 



The metamorphofis of infeds has been regarded as a fudden ope- 

 ration, becaufe they often burft their iliell or filky covering quickly, 

 and immediately appear furnifhed with wings. But, by more at- 

 tentive obfervation, it has been difcovered that the transformation of 

 caterpillais is a gradual procefs from the moment the animals are 

 hatched till they arrive at a ftate of perfedion. Why, it may be 

 afked, do caterpillars fo frequently caft their fkins ? The new fkin, 

 and other organs, were lodged under the old ones, as in fo many 



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