156 STATES OF INSECTS. (Larva.) 
vals into a series of rings or segments ; usually in num- 
ber, ¢welve ; often nearly equal in length, but sometimes 
in this respect very dissimilar?. The general outline or 
shape of the body is extremely various: most frequently 
it approaches to cylindrical, as in most of the caterpillars 
of Lepidoptera, and of the Hymenopterous tribe of saw- 
flies (Serrifera). The next most common figure is that 
more or less oblong or oval one, sometimes approaching 
to conical, found in many of the larvee usually called 
grubs; such as those of the weevil and of the capricorn 
and other coleopterous tribes; of bees, and all Hymenop- 
terous insects but the saw-flies; and also of a large num- 
ber of two-winged flies (Diptera). In some the figure ap- 
proaches to fusiform, as in most of the moths of the Fabri- 
cian genus Lithosia. In others, as in those of the water- 
beetles (Dytzscus, &c.), it approaches to an obovate shape, 
being widest towards the head, and terminating in a point 
at the anus. In others, again, it is linear; an example of 
which is that of Staphylinus. Some are convex, and 
others gibbous above, and flat underneath; as those of 
Silpha, Chrysomela and many other beetles. Others are 
flat, both above and below, and depressed like a leaf; 
a remarkable instance of which has been before noticed”. 
segments are to be seen; and in many coleopterous and dipterous 
ones the folds of the skin prevent the segments from being distinctly 
perceptible. 
* Reaum. ii. 361. In the larva of a small common moth often met 
with in houses ( Agdossa pinguinalis), every segment is divided into two 
parts, and underneath has two deep folds, by means of which these 
two parts can separate to a certain point, or approach again, accord- 
ing to circumstances. Thus Providence has enabled them to pre- 
vent their spiracles from being stopped by the greasy substances on 
which they often feed. N. Dict. d’ Hist. Nat. 1. 208. 
» See above, p. 110. 
