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HYMEX0PTKHA. 
an excessively small abdomen, which appears to spring 
from the upper surface of the thorax, instead of from 
the apex, the usual point of attachment. 
The family of the Ichneumonidw is very numerous, 
and contains insects both large and excessively minute. 
They are all parasitic on other insects, and in many 
cases are eminently useful, as active agents in the 
destruction of the numerous pests of the garden and 
farm. The name of Ichneumon, originally given to 
the carnivorous animal (Herpestes) of Egypt, because it 
“ tracked” or hunted afar the eggs of the crocodile, 
became applied to the Hymenopterous insect, from its 
habit of hunting for caterpillars, plant-lice, etc. These 
insects are distinguished by having the abdomen 
attached to the thorax at its hinder extremity, and 
between the base of the hind-legs, and often by a 
pedicel; the antennae are long and elegant; the ovi¬ 
positor is in some species external and of great length, 
in others it is short and concealed within the abdomen ; 
these structural differences intimate a difference of 
habit, for while some species deposit their eggs upon 
exposed larvae, others guided by some mysterious in¬ 
stinct, discover the habitat of some concealed grub, and 
by means of their long sting-like ovipositors, succeed 
in piercing through the concealing substance, and 
lodging their eggs within the body of their victim. 
The little Gall-fly grub may fancy itself snug and safe 
within the large oak-apple, but the Ichneumon fly can 
reach him ; neither is the wild bee secure within its 
cell, nor the beetle in its wooden retreat within the 
branch of some forest tree. There is scarcely a tribe 
of insects which is not subject to the attacks of these 
