On the BnmbifJIiiJ Fauna of South Africa {Dlptera}. 153 



iridescent. The 2 whitish hyaline fenestrae are rounded and are 

 placed one at the base of the 2nd longitudinal vein and one on the 

 middle cross- vein ; they are of about equal size ; at the base of the 

 3rd and of the 4th posterior cell there are less-developed yellowish 

 stripes ; at the end of the anal cell there is in addition a rounded, 

 yellowish spot. Basal hook and basal comb black, the latter with 

 a dark greyish tomentum above ; veins quite reddish yellow and paler 

 on the hyaline pai'ts of the wing ; 2nd longitudinal vein less looped 

 at end and not retreating, originating before the middle cross- 

 vein ; marginal cross-vein oblique; upper branch of the cubital 

 fork S-shaped. First posterior cell dilated outwardly, as broad as the 

 2nd ; 3rd broadly truncate at base ; 4th broader than the 3rd at end ; 

 discoidal cell narrowed in the middle, with the middle cross-vein 

 placed before the centre, and with the terminal cross-vein straight, 

 but set obliquely ; anal cell broadly open. Alula yellowish-brown, 

 with a darkish fringe like the base of auxiliary lobe, which is black on 

 its apical half only. 



B. GROUP NEMESIS. 



EXOPKOSOPA (EXOPROSOPA) NKBIESIS, Fabricius (1805). 

 Syst. Autl., 1805, p. 121. 



A very distinct species, characterised by the entirely black wings, 

 with a narrow whitish hyaline apex and some shining brownish spots 

 at cross-veins and bifucatious. 



A specimen from M'Fongosi, Zululaud, 1914 (W. E. Jones), and 

 another from Barbertou, Transvaal, December, 1911 (H. Edwards). 



C. GROUP SENICULUS. 



EXOPROSOPA (EXOPROSOPA) MOBosA, Loew (1860). 

 Dipteren-Fauua Siid-Afrikas, p. 332, pi. ii, fig. 30. 



A very characteristic species of great size, distinguished by the 

 abbreviated cross-baud of the wrings at the end of discoidal cell. 

 Originally described fromCaffraria.it is probable that Littorliy nclm s 

 hamatus, Macquart, from the Cape is the present species, chieflv 

 because the length of the proboscis seems to be variable, as observed 

 by Miss Kicardo for the following species. There is a female specimen 

 from Barberton, Transvaal, December, 1911 (H. Edwards). 



