TO THE LUANGWA VALLEY, NORTH-EASTEtlN RHODESIA. 311 



It must be remembered that at the time of writing (mid September) the 

 dry season, which is very marked in the low ground of the Luangwa Valley, 

 is nearly at its height^ and the first rains are due in from five to six weeks 

 time. The first signs of spring, obvious enough on the high and cool 

 plateau, are hardly discernible on the low ground. The appearance of 

 Tabanid^e in this locality would however appear to coincide with that of 

 the same or allied species elsewhere irrespective of elevation. 



Though a few isolated individuals have been taken on the banks of the 



Fig". 7. — Natives, with hippopotamus and crocodile, Luangwa River ; 

 the author's camp in the background. 



Luangwa River itself, the vast majority are to be found in the neighbour- 

 hood of the tributary streams and lagoons, now fast drying up, in which 

 they have no doubt spent their larval stages. 



During the hottest hours of the day numbers of both sexes (the males 

 however being in the majority) are to be found round the pools referred 

 to above, drinking at the damp sand or settled on the reeds near the water's 

 edge. Some of the more fragile and slender species, such as 1\ gratus and 

 a species allied to T, ditceniatus, seemed to be able to drink by alighting on 



