CECIDOMYIDAE. 7 



among Mycetophilidce. But the total habitus of the Zygonema 

 being more like that of the former than of the latter, and the tibial 

 spurs being so very short, that in some species they can only be 

 discovered by the closest scrutiny, I think I may be justified if I 

 add them to the Gecidomyidce, though in many respects they agree 

 with the genus Sciara, which has its natural place among the 

 Mycetophilidce. 



The whole family is divided into two sections. The first of 

 these, the Cecidomyina, have on the wings four longitudinal veins, 

 the two last of which often coalesce in the beginning of their course, 

 or are more or less incomplete. They have no ocelli, and the first 

 joint of their tarsi is much shortened. The genera belonging here 

 are : Hormomyia Loew, Diplosis Loew, Cecidomyia Latr., As- 

 phondylia Loew, Dirhiza Loew, Colpodia Winn., Epidosis Loew, 

 Asynapta Loew, Lasioptera Meig., and Clinorhyncha Loew. 

 In the genera of the second section, the Anaretina, between the 

 second and third of those veins of the wings which the first sec- 

 tion possesses, another longitudinal vein is inserted, being simple 

 only in Campylomyza, while it is furcate in all the other genera ; 

 the first tarsal joint is not shortened, and in all genera, with the 

 single exception of Cecidogona, there are distinct ocelli. To this 

 section belong: Campylomyza Meig., Cecidogona Loew, Ana- 

 rete Hal, Catocha Hal. (= Macrostyla Winn.), Lestremia 

 Macq. (= Diamesa Meig.), and Zygoneura Meig. 



I have omitted here the genera Heteropeza Winn, and Spani- 

 ocera Winn., not having had an opportunity of examining speci- 

 mens. Heteropeza seems to harmonize in many points with the 

 genera of the first section, but differs very strikingly by the totally 

 different structure of its tarsi. Rondani has established in this 

 family a good number of genera, which are, however, quite un- 

 available, since the observations on which they are founded are 

 too inexact. 



Very little information has thus far been published respecting the 

 Cecidomyidce of N. A. Most of the species sufficiently described 

 belong to the genus Cecidomyia in its restricted sense, as is now 

 in use ; viz : Gee. destructor Say, salicis Fitch, and tritici Kirby ; 

 Gee. grossularice Fitch ought, as it seems, to be referred to the 

 genus Asphondylia ; some fine species of the genera Diplosis 

 -and Lasioptera occur there. Out of the second section I have 



