102 GENERAL ZOOLOGY 



vicious-looking jaws. The larva is known by many names 

 (dobson, crawler, amly, conniption bug, clipper, water 

 grampus, goggle goy, bogart, helldevil, flip-flop, etc.), and 

 is often used by fishermen for bait. It is an inch or more 

 in length, has three pairs of legs and a fringe of slender gills 

 along either side of the abdomen. 



Order 13. Mecoptera. The scorpion-flies possess wings 

 similar to the Neuroptera; the head is prolonged ventrally 

 into a long beak which has biting jaws at its tip; metamor- 

 phosis is holometabolous. The common name refers to 

 the structure present in some species at the end of the male 

 abdomen which somewhat resembles the sting of a scorpion. 



Order 14. Trichoptera, Caddis-flies (Fig. 38). The 

 larvae of the insects in this order are the caddis-" worms " 

 which make little tubes or cases to protect the body. The 

 tubes are usually carried about with the larvae, but are 

 sometimes fastened to rocks or stones. They are character- 

 istic for each species, in regard to both materials and archi- 

 tecture. Some species make their cases entirely of snail 

 shells, others use sticks, leaves, sand, etc. Adult caddis- 

 flies have four membranous wings, covered with little hairs. 

 They live only a short time (long enough to mate and lay 

 eggs) but often occur in great numbers near bodies of 

 water where they passed their larval life. The mouth parts 

 of caddis-flies are rudimentary, as in may-flies. 



Order 15. Lepidoptera (Fig. 51). Here belong the 

 butterflies, skippers, and moths. These insects have four 

 wings covered with scales; the mouth parts form a long 

 sucking tube; all are holometabolous. 



The larvae of lepidopterous insects are caterpillars, which 

 often do damage by gnawing vegetation. The adults feed 

 largely on nectar, sucked out of flowers by means of the 

 long proboscis. When not in use the proboscis is coiled up 

 beneath the head. There are over 7000 species of Lepidop- 

 tera in the United States, and many are of great economic 

 importance. This vast array is divided into two sub- 

 orders : 



