THE CATERPILLAR 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 

 leathery brushes that project in front of the face. 



The mouth parts of the tent caterpillar moth are not 

 typical ot these organs of moths and butterflies in gen- 



Fig. 161. Moths ot'the tent caterpillar, Malacosoma amerhana. (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. Everyone is familiar with the large humming- 

 bird moths, or hawk moths, that are to be seen on summer 

 evenings as thev 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. 163 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 



[307] 



