METAZOA INSECTA. 451 



The legs are, in fact, so long that the insect never stands 

 upon them, and therefore never alights but suspends it- 

 self from a twig by its long fore legs, sometimes using also 

 its second pair. In this situation it has cleverly adapted 

 its hind legs for seizing, using them as hands (Brauer). 

 The mouth parts are better fitted for piercing than those 

 of Panorpa, and living insects, preferably flies, are the 

 diet. 



The wingless condition is represented in the Mecop- 

 tera by the female Boreus hiemalis (PL 1145), which is 

 sometimes found on snow. The head is extended into a 

 beak, as in the other Mecoptera, and the female has an 

 external ovipositor while the hind legs are adapted for 

 leaping. 



Order 13. TRICHOPTERA. 



The Phryganidae or caddis-flies are the only members 

 of the Trichoptera. The larvae are caterpillar-like from 

 the start, although their aquatic life (together with the 

 habit of carrying a protective case about with them) has 

 caused such modifications in structure that they are not 

 so strikingly like caterpillars as the larvae of Mecoptera. 

 They are, however, nearer the caterpillar than the Thysa- 

 nuriform type. 



The adults do not closely resemble the imagoes of any 

 of the orders so far described, but their resemblance to 

 moths of the order Lepidoptera is most marked. 



Anabolia is a common genus in New England. The 

 forward part of the body of the larva (No. 1146; PI. 

 1147, fig. i) is chitinous owing to exposure, while the 

 posterior part, being covered with a case, is soft and light 

 colored. The case (No. 1146; PI. 1147, fig. 2) in this 

 genus is made of sticks and stones, and is fastened to the 

 body by means of two hooks at the end of the abdomen, 

 while it is probable that the three tubercles on the first 

 abdominal segment also aid in this work. As the larva 



