01 SYRPIIID.*:. 



antennae, with a rounded prominent tubercle, which is united below 

 with the epistoma ; peristoma narrow, not produced ; lower posterior 

 orbits white pollinose and white pilose ; opening of the buccal cavity 

 broad, ovate. Thorax black, dark pollinose and with very short pale 

 hairs on the back, without distinct pattern, reddish on the humeri 

 and on the pro- and mesopleura ; scutellum dark reddish, with 

 short pale hairs. Squamulae pellucid, with a whitish fringe ; 

 halteres whitish. Abdomen elongate, almost cylindrical, gradually 

 attenuated behind; it is entirely black, dark grey pollinose, 

 brownish towards the end, with short grey hairs ; second and third 

 segments with a narrow yellow hind border ; venter grey ; genitalia 

 rounded, brownish red. The four front legs, including the coxae, 

 dark red, with black grey-pollinose tibiae and tarsi ; hind legs with 

 more blackish coxae and femora, which are greatly swollen and 

 bear black bristles, but are not toothed below ; hind tibiae curved, 

 reddish, the tarsi black. All the hairs on the legs are pale. Wings 

 narrow, greyish hyaline, very thinly pubescent ; costal cell yellow- 

 ish ; the black spot filling the ends of the marginal and submarginal 

 cells, not passing the third longitudinal vein, but touching the costa 

 in front and reaching the kink in the third vein ; marginal cell 

 shortly stalked ; kink in the third vein narrow and triangular, but 

 its fore branch straighter and more perpendicular than the hind 

 one ; small cross-vein curved and placed a little beyond the middle 

 of the discal cell ; vena spuria chitinized ; outer lower corner of the 

 discal cell rounded, not appendiculate ; second basal cell not 

 dilated at the end above ; anal cell dilated towards its middle. 



Type c? , a single rather old and badly preserved specimen from 

 South Africa (R. W. Plant}. 



Genus 17. HELOPHILUS, Meigen (1803). 

 Subgenus MESEMBEIUS, Rondani (1857). 



All the species in the collection belong to this subgenus, which 

 is very characteristic of the Ethiopian fauna, and they all have the 

 globiferous hairs at the base of the hind tarsi. They can be dis- 

 tinguished as follows : 



1 (10) Thorax with very sliarply defined black and 



yellow stride:; on the back. 



2 (5) Hind femora of the male without a brush- 



like tuft of black hairs on the inner side 

 near the base. 



3 (4) Middle tibiae of the male with the long- 



yellow pubescence present also on the 

 anterior side and extending only to the 

 first joint of the tarsi; hind tibiae black; 

 first yellow abdominal band of the female 

 interrupted in the middle capensis, Macq. 



4 (3) Middle tibiae of the male with the yellow 



pubescence only on the posterior side and 

 extending- to the four first joints of the 



