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. 161) 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 hot encumbered with implements 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 propupa (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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