86 DIPTEEA. 



a female), are decidedly silvery in the male. I have also seen four specimens in 

 Professor Bellardi's collection labelled Mexico (Sumichrast). 



N.B. — Professor Bellardi's collection contains two more species belonging to the 

 division of Exoprosopa with a closed and long petiolate first posterior cell, but they 

 are represented by single specimens in a very poor condition : — 



1. Specimen without head from Mexico (Sumichrast). This has a rather large round 

 brown spot on the bifurcation of the second vein, which spot coalesces with the rather 

 dark brown of the costa ; the veins at the base of the third and fourth posterior cells 

 clouded ; a broad white cross-band on the second abdominal segment, the seventh also 

 with white hairs ; the long hairs on the thorax and at the base of the abdomen more 

 yellow than red ; the posterior margins of the abdominal segments with fringes of short, 

 rufous hair, &c. Of the size of the larger specimens of E. limbipennis. 



2. A single specimen, without locality, 10-11 millim. long; with a broad yellowish- 

 silvery cross-band on the second abdominal segment, a narrower one on the fourth ; 

 traces of silvery hairs on the sixth and seventh segments ; the petiole of the first posterior 

 cell rather long; the stump within the discal cell; the wings with a pale brownish 

 tinge, the brown band of the costa not very dark ; the antennal style rather long, &c. 



Among the described South-American species the following seems to belong to this 

 group : — E. argentifasciata, Macq. Dipt. Ex. Suppl. i. p. 109 (Colombia). 



8. Exoprosopa rostrifera, s $ . 



Exoprosopa rostrifera, Jaennicke, Neue exot. Dipt. p. 33, t. 2. f. 19. 



Hab. Mexico, Northern Sonora (Morrison), Oaxaca (Sumichrast, coll. Bellardi). 



The description agrees well : the white scaly hairs on the last abdominal segment 

 are almost silvery in some specimens, and much less so in others ; white hairs are also 

 visible along the posterior margin of the penultimate, and on the lateral margins of 

 segments 3 to 6. The stump of a vein within the discal cell, which appears (I. c.) on 

 the figure, but is not mentioned in the description, is absent in most specimens. The 

 third antennal joint is elongate conical, the style at its end is as long, or longer, than 

 the joint. Length 12-13 millim. Eight males, two females. 



N.B. — The broad white cross-band on the second segment, which is not narrowed 

 in the middle, and therefore has nearly parallel sides, renders this species easily 

 recognizable. There is a specimen in the British Museum in which the first posterior 

 cell is closed in one wing, very narrowly open in the other. 



9. Exoprosopa filia, sp. n., e $ . 



Very like E. rostrifera, but certainly different : — 1, the proboscis is much shorter, projecting less than the length 

 of the head beyond the oral margin : 2, the size is smaller, 10-11-5 millim. : 3, the wings are compara- 

 tively shorter and broader : 4, the cloud on the posterior cross-vein is a little larger, and there is a vestige 

 of a cloud at the proximal end of the third posterior cell, much more distinct than in E. rostrifera : 5, the 



