ALDRICH : DOLICHOPODID.K OF GRENADA., W. I. 85 



DIAPHORUS. 



Meigen, Syst. Beschr., IV, 1824. 

 Loow, Mon. N. A. Dipt., II, 156, 1864. 



In attempting to separate this genus from Chrysotus, which 

 it often greatly resembles, I have followed these rules : First, 

 to assign to Chrysotus all species in which the eyes of the male 

 are approximated below the antennae, and to Diaphorus all in 

 which they are approximated above; second, of the consider- 

 able number of species in which there is no approximation, to 

 refer to Chrysotus all in which the male does not have a group 

 of large bristles at the apex of the abdomen. 



In my preceding paper on the Dolichopodidse of St. Vincent, 

 I made a bad blunder in failing to recognize Diaphorus spec- 

 tabilis Loew, which I redescribed as D. approximatus . I have 

 since found further that the numerous females which would 

 almost inevitably accompany "numerous males" in a collec- 

 tion were mixed up with the females of Lyroneurus simplex Aid., 

 and they are there yet, as I am unable to find any characters 

 for their separation. The two species being nearly, if not en- 

 tirely, indistinguishable in the female sex, it seems evident that 

 the genus Lyroneurus is insufficiently characterized, and I have 

 accordingly abandoned it. Loew himself (Mon. N. A. Dipt., II, 

 169) was a little staggered when he came to compare the genus 

 with some North American species of Diaphorus ; but with the 

 material then known it still seemed tenable. It would certainly 

 be an anomaly, however, if two females not distinguishable from 

 each other would have to be placed in separate genera. 



l 



Table of West Indian Sx>ecies of Diaphorus. 



( Femora yellow 2 



/ Femora black or brown 5 



a \ Fore coxa? with a row of three long bristles dimidiatus Aid. 



' \ Fore coxae with only small bristles 3 



o \ Male with very large pendent white palpi amamus, n. sp. 



' / Male with only ordinary palpi 4 



( Eyes of male not approximated ])arvidus Aid. 



4. - Eyes of male approximated, tarsi infuscated (Cuba). . . subsejunctus Loew. 



( Eyes of male contiguous, tarsi not or scarcely infuscated flavipes Aid. 



f Color green, shining G 



r J Color black, but little shining, wings deeply infuscated opacits Loew. 



i Color black, dorsum gray pollinose, opaque, wings but little 



clouded contiguus Aid. 



P \ Eyes of male approximated sjjcctabilis Loew. 



' / Kyes of male not approximated 7 



( Male with a long erect bristle on the under side of the hind 



7. -] metatarsus simpler Aid. 



( Male without such bristle diibius Aid. 



{Parvulua and subsejunctus are not represented.) 



