THE HESSIAN-FLY. 
the larva state. They 
may be recognized as 
greenish maggots living 
among groups of plant- 
lice. 
In the two-winged gall- 
flies (Fig. 345, Cecedomyia 
destructor Say, or Hes- 
sian-fly) the body is small 
and slender, with long 
antenne. The crane-flies 
(Tipula) 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 
puparium 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 maxille 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 
35% 
Fig. 845,—Hessian-fly. a, larva; b, pupa; 
c, incision in wheat stalk for larva. (Mag- 
nified).—After Fitch. 
Fig. 346.—A, 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, antenne; lbr, labrum; h, 
hypopharynx; m, mandibles; mz, maxille; 
map, maxillary palpus; lb, labium: ce, ely- — 
peas. (Magnified.) 
