The genus Ibalia contains at present, I believe, no other species 

 than Cultellator, and was never known to inhabit Britain until the 

 male represented in the plate was captured flying in a garden at 

 Bungay, Suffolk, by Mr. W. H. C. Edwards, justly celebrated for 

 his masterly engravings and knowledge of the fine arts. It is also 

 found in Germany and the South of France. M. Latreille found 

 it in the environs of Brive, in a wood of old Horn-beams, vaulting 

 round some of the trees, in the month of May : M. Foudras also 

 takes it near Lyons. The economy and habits of this genus are 

 supposed to be similar to the rest of the family, forming galls upon 

 various plants. 



The eccentric structure of the third joint of the antennae in the 

 male at once shows that Ibalia belongs to the Diplolepida;'^, of 

 which family it is the largest species; the second submarginal cell 

 is so minute, that it is scarcely discernible through a lens; the 

 hinder legs in both sexes are very powerful, and exceedingly dis- 

 prqportioned to the body and other legs, which are remarkably 

 small. Ibalia is nearly allied to Cynips (pi. 688), but it is readily 

 distinguished by the length of the abdomen and the neuration of 

 the wings. The singular spine on the second joint of the hinder 

 tarsi of both sexes, as well as the puncture or spiracle on the side 

 of the abdomen, has hitherto, I believe, escaped the observation of 

 authors. 



It may be here observed, that the mandibles are often not coun- 

 terparts of each other, tlie shape being adapted to their close con- 

 tact when at rest; other parts of the mouth are also sometimes ir- 

 regularly formed. The student must not be misled by these excep- 

 tions, which are most frequent in the Hymcnoptera^ occasionally 

 in the Coleoptcra, and probably all the Mandibulat(e. 



The plant figured is SteUaria jiiedia, Common Chick weed. 



* This family ought to have been called Cynipidce, but having adopted La- 

 treille's term, it has been tliought better to retain it through the work to prevent 

 confusion. 



