424 ON THE TRIBES 



erred in his analysis of the mouth of these last animals, 

 they must then no doubt take a situation near to the 

 Diptera. But at present, all who confide with me in the 

 consummate accuracy of this gentleman's microscopical 

 dissections can only consider the resemblances which the 

 Strepsiptera bear to certain Haustellata as so many re- 

 lations of analogy. M. Latreille seems to have been in- 

 duced originally to form his opinion of their affinity to 

 Dipterous insects, from an idea that the head of their 

 larva? is soft and changeable in form ; which, if correct, 

 would indeed have been conclusive evidence in his favour. 

 I can perceive nothing, however, either in the figure or 

 slight description given of the larva of Xenos Peckii, by 

 professor Peck, or in the more detailed and scientific 

 history of the larva of the Xenos vesparum of Rossi by the 

 late M . Jurine*, that warrants any other opinion on the 

 subject than that the head is covered with a hard scale, 

 and is constant in form like that of Hymenoptera. M. La- 

 treille is at last sensible of this, and says, " Outre que les 

 larves des Jlhipiptlres ont une veritable tete muniede deux 

 yeux ; qu'elles ressemblent d'avantage aux larves apodes 

 de la plupart des Hymenopthes, elles conservent leur 

 forme primitive, on rieprouvent point le changement que 

 Reaumur nomme forme de boule allongee. 



I have elsewhere shown that Mr. Kirby considers these 

 insects as close to the Coleoptera. Better authority, there- 

 fore, for this affinity 1 need not. It only remains to de- 

 monstrate their affinity to the Hymenoptera. From their 

 comparative anatomy and metamorphosis, Jurine was the 

 first to prove this, the opinion of Rossi, with respect to 



• It was one of the last papers read by this lamented naturalist before 

 the society established at Geneva for the promotion of Natural Science. 



