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



DIAPHORUS. 



Meigen, Syst. Beschr., IV, 1824. 

 Loew, 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 antenna, 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 ray preceding paper on the Dolichopodidffi of St. Vincent, 

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

 tahilis 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. 



Table of West Indian Sjiecies of Diaphorus. 



-. <i Femora yellow 2 



■ 1 Femora black or brown 5 



tj \ Fore coxae with a row of three long bristles diinidiatus Aid. 



" ■ X Fore coxfe with only email bristles 3 



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



■ / Male with only ordinary palpi 4 



( Eyes of male not approximated pari^^/^Ms Aid. 



4. -j Eyes of male approximated, tarei infuscated (Cuba). . . subsfjitnctus Loew. 



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



r Color green, shining 6 



f- J Color black, but little shining, wings deeply infuscated opaciis Loew. 



■ 1 Color black, dorsum gray pollinose, opaque, wings but little 



t clouded confif/uus Aid. 



Q \ Eyes of male approximated siiectabilis Loew. 



■ } Eyes of male not approximated 7 



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



7 . -j metatarsus simplex Aid. 



( Male without such bristle dubius Aid. 



{Parvidus and subsejunctus are not represented.) 



