THE HESSIAN-FLY. 



357 



the larva state. They 

 may be recognized as 

 greenish maggots living 

 among groups of plant- 

 lice. 



In the two- winged gall- 

 flies (Fig. 345, Cecidomyia 

 destructor Say, or Hes- 

 sian-fly) the body is small 

 and slender, with long 

 an te n n ae. The crane-flies 

 (Tipitla) are large flies, 

 standing near the head 

 of the order, and, like 

 the gall - fly, the chry- 

 salis has free append- 

 ages, there being no 

 pupavium or pupa-case, 

 as in the lower flies. 

 Lastly, we have the mos- 

 quito (Figs. 346 and 347), 

 whose larva is aquatic, 

 and breathes by a process 

 on the end of the body, 

 containing a trachea. 



Order 15. Lepidoptera. 

 The butterflies and 

 moths form a well-defined 

 group, and are known by 

 their scaly bodies (Fig. 

 348), the spiral maxillae or 

 tongue, rolled up between 

 the two large labial palpi, 

 and their usually broad 

 wings. As the butterfly, 

 +-he type of the order, has 

 been described at some 

 length, we will only 

 enumerate some of the 



Fig. 345. Hessian-fly, a, larva; 6, pupa; 

 c, incision in wheat stalk for larva. (Mag- 

 nified). After Fitch. 



B 



Fig. 346.^!, larva; c, its respiratory tube. 

 B, pupa; d, respiratory tube; a, two paddles 

 at the end of the body. 



Fig. 347. Head and mouth parts of mos- 

 quito, e, eye; a, antennae; Ibr, labrum; h, 

 hypopharynx ; m, mandibles; mx, maxillae; 

 mxp, maxillary palpus; Ib, labium; c, cly- 

 peas. (Magnified.) 



