198 THE CANADIAN ENTOMOLOGIST. 



certain strictures* on our recent work have appeared. The critic seems 

 to have overlooked the fact that the descriptions referred to in particular 

 are simply preliminary ; he was presumably unaware that they are based 

 upon detailed descriptions, and appears to have ignored the fact that 

 most species bear excellent generic and specific characters, and that a 

 number, at least, can under no circumstances be associated with any 

 vegetable deformation. There is no reason why adults of this group 

 should not be studied independently of the earlier stages any more than 

 in the Hymenoptera, Lepidoptera and other orders. It is regrettable that 

 there must inevitably be some confusion between a system which, sooner 

 or later, will break down on account of its own limitations, and the intro- 

 duction of one based upon well-accepted systematic principles. The 

 earlier the change is made, the better for this branch of entomology, and we 

 hope shortly to have the pleasure of demonstrating the wisdom of this course. 



THE CLASSIFICATION OF THE CULICID.4£. 



BV EVELYN GROESBRF.CK MITCHELL, WASHINGTON, D. C. 



In Dr. Williston's article under the above head (Can. Ent., Dec, 

 1906), he advocates uniting the Corethridjc and Dixid;« with the Culicidae. 

 Yet Schiner, praised by Dr. Williston as a model systematist, erected the 

 family Dixida?, while Brauer, whom Williston condemns, was in favour of 

 its union with the Culicidse. 



Why should the Corethridsv, whose larvae and pupae differ greatly in 

 structure and habits from those of the Culicidse, be j^laced in the latter 

 family? Not only do the early stages differ, but the moiUh-])arts of the 

 adults, admittedly of importance in the clissification of the Diptera, are not 

 fitted for biting, and are com])aratively short, in contradistinction to the 

 long Culicid proboscis, which is so constructed as to enable not only 

 the females but also males of certain genera to obtain blood. The palpi of 

 Corethridae are slender, very flexible and strongly recurved, whereas in the 

 Culicidie the palpi are robust, almost straight, rigid and directed forward. 

 Corethridae are said to deposit their eggs in a mass of gelatin, a method of 

 oviposition unknown among the Culicidae, and their pupae float submerged 

 or, in the case of Corethrella, on the surface, not being active like those 

 of Culicids. 



Mr. M. T. Thompson, of Clark University, who has been making 

 special comparative studies of the internal anatomy of the adults and larvae 

 of many of the Diptera, the results of which he intends later to i)ublish, 

 has very kindly mformed me of some of these results, giving permission to 



'1907. — Beutenmueller, Wm., new species of Gall-producing Cecidomyiidie. 

 Amer. Mus. of Nat. Hist. Bull., Vol. 23, Art. 18, p. 385-400. 

 June, 1907 



