VUl 



Genus Glossina 



TSETSE FLIES* 



Abdomen generally, but not always, has pale 

 but well-marked dark-brown bands interrupted in 

 the middle. 



1. Dull-coloured, brownish flies, seven to 

 twelve mm. long (excluding proboscis and 

 wings). 



2. Wings in resting position, closed flat, one 

 over the other, scissors-like, projecting beyond 

 the abdomen. 



3. Proboscis ensheathed in palpi, projecting 

 horizontally in front. 



4. Base of proboscis suddenly expanded into 

 a large onion-shaped bulb. 



5. Arista feathered on upper side only. 



6. Male genitalia (hypopygium) highly cha- 

 racteristic, oval and tumid, with a vulviform 

 median groove (anus) running from anterior 

 margin to beyond the middle. Sex easily distin- 

 guished by this mark. 



7 . Win gs absolutely characteristic, especially 

 in the , course of the fourth longitudinal vein 

 {vide Fig. 96, iv). The anterior transverse vein is 

 very oblique. The bend in the course of the 

 fourth vein, before it meets the anterior transverse 

 vein, is absolutely diagnostic. 



'^ The data of this section are compiled from A Monograph of the Tsetse Flies, 

 by E. E. Austen, and from an article in the British Metrical Journal, September 17, 

 1904, by E. E. Austen. 



