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INSECT ARCHITECTURE. 



by rolling up the lilac leaf into the form of a gallery, 

 where it may feed in safety. We have repeatedly seen 

 one of them when just escaped from the egg, and only a 

 few lines long, fix several silk threads from one edge of 

 a leaf to the other, or from the edge to the mid-rib. Then 

 going to the middle of the space, he shortened the threads 

 by bending them with his feet, and consequently pulled 

 the edges of the leaves into a circular form ; and he 

 retained them in that position by gluing down each thread 

 as he shortened it. In their younger state, those cater- 



Another nest of Lilac-leaf Roller. 



pillars seldom roll more than a small portion of the leaf ; 

 but, when farther advanced, they unite the two edges 

 together in their whole extent, with the exception of a 

 small opening at one end, by which an exit may be made 

 in case of need. 



Another species of caterpillar, closely allied to this, rolls 

 up the lilac leaves in a different form, beginning at the 

 end of a leaf, and fixing and pulling its threads till it gets 

 it nearly into the shape of a scroll of parchment. To 

 retain this form more securely, it is not contented, like the 

 former insect, with threads fixed on the inside of the leaf; 



