CATERPILI.AR AND THE MOTH
reduced to mere rudiments in the adult, where they appear as two insignificant though movable knobs (Fig. 162, Mx). The median part of the labium has been reduced to almost nothing in the moth; but the labial palpi (LbPlp) are long and three-segmented, and when normally covered with hairlike scales they form two conspicuous feathery brushes that project in front of the face. The mouth parts of the tent caterpillar moth are hOt typical of these organs of moths and butterflies in gen-
Fro. ?6?. Moths of the tent caterpillar, Malacosoma americana. (A little greater than natural size)
eral, for most of these insects are provided with a long proboscis by means of which they are able to feed on liquids. Evervone is familiar with the large humming- bird moths, or'hawk moths, that are to be seen on sumnaer evenings as they dart from flower to flower, thrusting into each corolla a long tube uncoiled from beneath the head; and we have all seen the sunlight-loving butterflies carelessly flitting over the flower beds, alighting here and there on attractive blooms to sip the sweet liquid from the nectar cups. Moths and butterflies carry the proboscis tightly coiled, like a tiny watch spring (Fig. I63 A, Prb), be- neath the head and just behind the mouth. It can be unwound and extended (B, Prb) whenever the insect wants to extract a drop of nectar from the depths of a
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INSECTS
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