to THE LITANGWA VALLEY, NORTH-EASTERN RHODESIA. 309 



itself a tributary), enters the Liiangwa at this point *. Though this stream 

 dries up in the dry season, there is a small s[)ring in its bed close to 

 Hargreaves. 



Since writing the above, I have received a note from Mr. Rennie, that 

 a single specimen of G. fasca has been taken biting a native on the banks 

 of this stream at Hargreaves. The time of day is not stated. 



I think it probable that this species Avill be found in small numbers during 

 the rains on most of the tributary streams and perhaps on the main river 

 itself. That it can be at all abundant even at this season seems unlikely, as 



Fig. 5. — Eocky bed of Southern Nyamaizi Kiver, south of the Mvuvia River, 

 Lower Luaugwa Valley. 



it does not seem to have been observed by either Dr. Leach or Mr. Silverlock 

 at that time of year. Dr. Kinghorn, who visited this place, I believC; about 

 June, 1907, does not seem to have met with it either. 



This species would appear to retire up the streams with the advance of 

 the dry season, and at the hottest and driest time it seems to be found only 



* Previously published maps are incorrect in this particular, as the Mvuvia does not enter 

 the LLiang;\Ya some miles below Hargreaves, as thero depicted, but at a point only some 

 200 yards above it. 



