Ill 



COCOON, PUPA, AND MOTH 



PUPATION, or the act of becoming a pupa, is out- 

 wardly much like molting. The caterpillar stops 

 eating, stays quiet for a day or so, empties its intestines, 

 and crawls about rapidly in search of a place to spin 

 its cocoon, or to burrow in the earth or in soft wood, 

 according to the habit of its species. 



Cocoons vary much in size, shape, plan of construc- 

 tion, and texture, and different shapes, sizes, and tex- 

 tures may be found even among the cocoons of the 

 same species. 



The larvae which burrow in the earth do so by push- 

 ing the dirt aside with their heads, making no pile at 

 the mouth of the burrow, but apparently packing the 

 dirt solid as they advance. When a caterpillar has 

 gone as far down as it wishes, it pushes the earth on 

 all sides with its head until it has made a little cave 

 or cell large enough to turn in, and with no passage 

 to the air. In this cell it lies, growing shorter 

 as the changes go on under the skin, and exuding a 

 rather gummy fluid which is absorbed by the earth 

 and keeps it from crumbling down on the larva, 

 although we have never found a cell which could be 

 taken out of the earth unbroken. We have tried many 



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