130 SOCIAL HABITATIONS. 
pod itself deformed. Mr. Westwood has described a species 
of gall-fly which infests the turnips, and another species is 
known to lay its eggs upon wheat. 
As if to show that the family of Cynipide is really 
related to the ichneumons, it has been discovered that 
some species of this family are actually parasitic upon 
other insects, In treating of this remarkable fact, Mr. 
Westwood writes as follows:—“The relations of these 
insects with the following families (i... Evanide and 
Ichneumonidz) have been already noticed. It had al- 
ways appeared to me contrary to nature that a tribe of 
vegetable-feeding insects should be arranged in the midst 
of parasites; nor was it until I had an opportunity of 
ascertaining the parasitic habits of some of the species of 
the family, that I was enabled to form a just notion as 
to the true value of the parasitic or herbivorous nature 
of these insects. In June 1833, I detected a minute 
species, Allotria victriz, in the act of ovipositing in the 
body of a rose-aphis, and I subsequently succeeded in 
hatching specimens of the perfect insect from infested 
aphides.” 
A figure of the tiny insect is given, as it appeared 
while in the act of depositing its eggs, and has a rather 
remarkable effect, from the fact that the very minute 
dimensions of the parasite make the aphis look quite a 
large insect. Other species of this family are also known 
to be parasitic. The rose-aphis is certainly infested by 
two species of gall-fly, and probably by more, while the 
aphides which are found on the willow, the cow-parsnip, 
and other plants, also fall victims to the Cynipide. 
There is one genus of this family, called Figites, which is 
parasitic on the larva or pupa of certain dipterous insects. 
The Cynipide are not the only insects that produce 
