THE HESSIAN-FLY. 



377 



The fleas (349) are 

 wingless flies, allied to 

 winged forms intermedi- 

 ate between the house- 

 flies and crane-flies. 



In the two- winged gall- 

 flies {Gecidomyia, etc., 

 Fig. 350, a tritici, Hes- 

 sian-fly) the body is small 

 and slender, with long 

 antennas. The crane-flies 

 (Tiptila) are large flies, 

 standing near the head of 

 the order, and, like the 

 flea and gall-fly, the 

 chrysalis is enclosed in a 

 cocoon, there being no 

 puparium or pupa-case, 

 as in the- lower flies. 

 Lastly, we have the mus- 

 quito (Figs. 351 and 352), 

 whose larva is aquatic, 

 and breathes by a process 

 on the end of the body, 

 containing a trachea. 



Order!. Lepidoptera. — 

 The butterflies and moths 

 form a well-defined group, 

 and are known by their 

 scaly bodies (Fig. 353), 

 the spiral maxillae or 

 tongue, rolled up between 

 the two large labial palpi, 

 and their usually broad 

 wings. As the butterfly, 

 the type of the order, has 

 been described at some 

 length, we will only 

 enumerate some of the 



Fig. 351. — A, larva ; c, its respiratory tube. 

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

 at the end of the body. 



352.— Head of Mosquito enlarged, n, 

 antefmoB ; m, mandibles ; mx, maxilla ; mp, 

 maxillary palpi; Ig, labium. 



