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B. MOISER — DESCRIPTION OF HAUNTS OF GJLOSSINA 



that I was obliged to move further away, and even at a distance of half-a-mile a 

 few flies were seen, which had probably followed us from the river. 



It was noticed that all the men adopted the same method of catching the flies, 

 namely, after first allowing the fly to bite freely, a broad-bladed knife was 

 cautiously brought up from behind, and carefully placed over the hind tarsi. 



Fig. 3. — Native catching Gloss/na tachiiwides with a knife, at Wajerou, Hawal River, 

 South Bornu. 



After alighting on the bare skin of the native — nearly always in the region of 

 the lower legs and ankles — the flies waited for about J of a minute before piercing 

 the skin, and then they quickly filled themselves with blood, and if undisturbed 

 they took to wing again within two minutes, or less. On several occasions, I 

 observed blood-stained fluid escaping from the hind-gut before the fly had finished 

 its meal. 



The bites of the flies caused a good deal of itching, Avhich lasted well into the 

 next day, but there was no noticeable local swelling of the part. All the speci- 

 mens collected were identified by Mr. Austen as G. tachinoides, with the exception 

 of one, which was G. morsitans. 



It seems probable that the tsetse-flies have inhabited the course of this river, 

 for a distance of ten miles or more, for a considerable number of years, and they 

 do not appear to have spread very much, the "belt" being a strictly local one. 

 Unfortunately I was able to spend only two days (21st and 22nd July) in this 

 vicinity. 



Another tsetse-belt was found in Bornu, this time all the specimens collected 

 (about 80 in number) being G. tachinoides, as identified by Mr. J. J. Simpson, 



