3t2 STRANGE DWELLINGS. 



and solid, and the 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 tliat the family of Cynipidae 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.e. Evanidae 

 and Ichneumonidae) have been already noticed. It had always 

 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 para- 

 sitic 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 para- 

 sitic or herbivorous nature* of these insects. In June, 1833, 

 I detected a minute species, Allotria vicirix, 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 Cynipidae. There is one 

 genus of this family, called Figifes, which is parasitic on the 

 larva or pupa of certain dipterous insects. 



The Cynipidae are not the only insects that produce galls 

 upon different plants. For example, several species of beetle 

 are known to pass their earlier stages in swellings produced by 

 the puncture of the parent insect. There is a little weevil of a 

 greyish brown, which is mentioned by Mr. Rennie, as forming 

 a gall upon the hawthorn. 



' In May, 1829, we found on a hawthorn at Lee, in Kent, the 



