INSECTS 



ments, the mandibles, with its discarded overalls; but it 

 has turned chemist and needs no tools. The glands that 

 furnished the silk for the larva have shrunken in size and 

 have taken on a new function; they now secrete a clear 

 liquid that oozes out of the mouth of the moth and acts 

 as a solvent on the adhesive surfaces of the cocoon threads. 

 The strands thus moistened are soon loosened from one 

 another sufficiently to allow the moth to poke its head 

 through the cocoon wall and force a hole large enough to 

 permit of its escape. The liquid from the mouth of the 

 moth turns the silk of the cocoon brown, and the lips of 

 the emergence hole are always stained the same color — 

 evidence that it is this liquid that softens the silk — and 

 the frayed edges of the hole left in the cocoon of the tent 

 caterpillar show many loose ends of threads broken by 

 the moth in its exit. 



The most conspicuous features of the moth (Fig. 16 1) 

 are its furry covering of hairlike scales and its wings. 

 The wings are short when the insect first emerges from 

 its cocoon (Fig. 159 J), but they quickly expand to normal 

 length and are then folded over the back (Fig. 161 A). 

 The colors of the moths of the tent caterpillar are various 

 shades of reddish-brown with two pale bands obliquely 

 crossing the wings (Plate 14 G, H). The female moth 

 (Plate 14 H, Fig. 161 B) is somewhat larger than the male, 

 her body being a little over three-fourths of an inch in 

 length, and the expanded wings one and three-fourths 

 inches across. 



The tent caterpillars perform so thoroughly their duty 

 of eating that the moths have little need of more food. 

 Consequently the moths are not encumbered with imple- 

 ments of feeding. The mandibles, which were such large 

 and important organs in the caterpillar (Fig. 152, Md) 

 but which shrank to a rudimentary condition in the pro- 

 pupa (Fig. 159 H, Md), are gone entirely in the moth 

 (Fig. 162). The maxillae, which were fairly long lobes 

 in the propupa (Fig. 159 H, Mx), have likewise been 



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