AA MODERN CLASSIFICATION OF INSECTS. 
out of the hole; should, however, the insect by chance escape the 
murderous jaws of its enemy, the latter immediately commences 
throwing up the sand, whereby, not only is the hole made deeper, and 
its sides steeper, but the escaping insect is probably hit, and again 
brought down to the bottom of the pit. It is chiefly upon ants and 
other soft bodied insects that these larvee feed. They are, however, 
capable of undergoing long fasts ; for one of my larva remained from 
October till March without food. It has been supposed that, as the 
food of these larvee consists entirely of juices, and as they appear to 
be destitute of anal aperture, the whole of their food is assimilated. 
M. L. Dufour has, however, traced the intestinal canal terminating in 
an anus, which is, indeed, very difficult to discover. (Ann. Soc. Ent. 
de France, tom. ii. p. 67. app.) Latreille states that these larvee are 
produced in the summer or autumn, and become pupz in the following 
spring. I found the larvee of all sizes in July, one of which became a 
pupa, and assumed the perfect state ; whilst another, of equal size, re- 
mained through the winter in the larva state. Previous to assuming 
the pupa state, the larva forms a globular cocoon of less than half an 
inch in diameter (fig. 63.17.) of fine sand, glued with silken threads 
spun from a slender telescopic-like spmneret, placed at the extremity 
of its body (fig. 63. 16.), and lined with fine silk. The pupa* (fig. 
63. 18.) is small, not being half an inch long, inactive, and with all the 
limbs Jaid at rest upon the breast. When ready to assume the perfect 
state, it uses its mandibles( fig. 63.19.), which are quite unlike those of 
the larvaand imago, and which have not been before described+, to gnaw 
ahole through the cocoon, and pushes itself partly through the aper- 
ture, in which it leaves the pupa skin ( fig. 63.17.). Immediately on as- 
suming the perfect state, the abdomen is almost immediately extended 
to nearly three times its previouslength. Rosel (Zns. Belust., t. iii. t. 1 7— 
21.); Reaumur (Mémoires, tom. vi. pl. 32—34.) ; Percheron ( Guérin 
Mag. Zool., p.59.); Disderi (in Turin Trans., tom. ili.) ; Bonnet ( Observ. 
* Mr. Guilding observes of Formicaleo (a genus separated by Leach from Myr- 
meleon), “ Nympha dum nocte declaratur, acetabulum elongatum emittens,” and in a 
subsequent page he seems to regard the acetabulum as analogous to the meconium 
of many animals, noticing also its chemical composition. _Reaumur has also noticed 
it. (Mém., tom. vi. p. 372.) 
+ Reaumur states that it is after the insect has become an imago that it gnaws a 
hole through the cocoon and escapes; but, as the pupa skin is found half protruded 
through the orifice, it is clear that it is whilst a pupa that this opening is made: 
indeed, this is the only use the pupa has for its mandibles, 
