324 INSECTA. 



thorax, and setaceous, with the two first joints thickest. There are 

 always three ocelli, the anterior or intermediate of which is the 

 smallest. 



BoLiTOPHiLA, Hoffm. Meif]., 

 Where they are arranged in a transverse \\n<\ 



M. Guerin has published a detailed description of a species of 

 this subgenus, in the Am. des Sc. Nat., X. Its larvae lives in the 

 mushroom *. 



Ma CROC ERA, Meiy., 

 Where the ocelli form a triangle f . 



Sometimes the antennae, even of the males, are, at most, as long as 

 the head and thorax. 



Some subgenera, in which the eyes are always entire,' are removed 

 from the others by their four posterior tibiae, all furnished exteriorly 

 with small spines, as in 



Mycetophila, Tl/eiijf., 

 Where there are but tv/o ocelli, very small and distant J, and in 



Leia, Meig., 

 Differing from Mycetophila in their three approximated ocelli, the 

 anterior of which is the smallest §. 



SciopHiLA, Meig. 

 The Sciophilse have the joints of their antennae, less croAvded, or 

 more distinct than those of the Leite, and they are also hairy. Besides 

 the closed cell which extends from the base to the middle, their v.'ings 

 present another complete cell, which is small, and corresponds to the 

 first of those termed cubital in the Hymenoptera ||. 



From the subgenera in which the outer margin of the tibiae is des- 

 titute of spines, and where there are ahvays three approximated 

 ocelli, we will first separate those in which the antennae are composed 

 of sixteen joints. 



Here the eyes are entire, and without any remarkable emargi- 

 nation % 



Platyura, Meig. 



To which he improperly unites the Ceraplatei. These Insects, in 

 their wings and carriage, greatly resemble the Sciophilae ; but their 

 first cubital cell is much larger ; their antennae seem to be propor- 

 tionally thicker and more compressed than those of the last subge- 

 nera, and even slightly perfoliate. The abdomen of the females is 

 widest near the end **. 



Synapha, Meig., 

 Where the wings present but a single cubital cell, closed by their 



* Meig., Dipt. I, 155. 

 f Meig., Ibid. 

 X Meig. Ibid. 



§ Lat., Meig., Miicq., and the Encyc. Method., 

 II Meig., Ibid. 



^ Meig., Ibid, and Macq., Dipt, du noid de !a France. 

 ♦» Meier Ibid. See Macq., Dipt du nord de la France. Tiprilaircs, p. 45. 



