212 



SYSTEMATIC ZOOLOGY 



The caddice flies are better known to the ordinary observer 

 in their larval condition, when thev are called caddice worms 

 (Fig. 213). The adult is a mothlike insect, with wings and body 

 thickly covered with hairs, and often with very long antenna:. 

 The larvae are wormlike animals living in the water in streams 

 or ponds, and conspicuous because of the great variety of tube- 

 shaped houses that they build for themselves out of small stones 

 or sticks or leaves. The parts are held together by delicate 

 threads of silk which the larvae spin from their mouths ; the 

 tubes are also lined with silk, and in some cases the tube is 

 formed entirelv of this material. 



Order 6. Lepidoptera 



The Lepidoptera (Gr. Xeiri's, scale, and irrepov, wing), or scaly 

 winged insects, constitute the most sharply defined order of 

 Hexapoda. They have two pairs of membranous wings, which 



Fig. 214. Piens rap e. a, larva or caterpillar; *, pupa; -f, male adult butterfly or imago. 

 (After Riley, from Parker and Haswell's Manual.) 



are covered with overlapping scales arranged in more or less 

 regular rows. The body of the insect is covered with very tine 

 hairs, in some species relatively long, and these occur at times 

 on portions of the wings ; the scales are to be regarded as short, 

 flattened hairs. The mouth parts are adapted for sucking; the 

 mandibles are rudimentary, and the maxillae usually form a 

 proboscis, sometimes very long and spirally coiled when not in 

 use. In this order the metamorphosis is complete. Its mem- 

 bers are called moths, skippers, and butterflies. The legs are 

 of use chiefly for supporting the body while at rest, and in many 



