﻿284 S. A. NEAVE — NOTES ON THE BLOOD-SUCKING 



Genus Silvius, Mg. 

 Silvius fallax, Aust. 



This interesting, recently described species was taken in very large numbers 

 during September and the beginning of October in the lower Luangwa Valley, 

 North-Eastern Rhodesia. The numbers in which it occurred may be realised by 

 the fact that 78 males and 298 females were captured during this period. In 

 spite, however, of these large numbers it was not much in evidence, unless 

 specially looked for in the neighbourhood of water-holes, and nearly all the above 

 specimens were taken under these conditions. The females were very ready to 

 bite natives drawing water at these places, but did not seem to be troublesome at 

 any appreciable distance from the water. At the same time the conditions 

 were somewhat exceptional, there being an average shade temperature at midday 

 of over 110° Fahr., and an intensely dry atmosphere. 



Genus Aegophagamyia, Aust. 

 Aegophagamyia pungens, Aust. (PI. XI, fig. 10.) 



I originally took a single female of this interesting and recently described 

 insect on some mangroves on the beach at Lamu, British East Africa, in 

 February 1912. Subsequently I found it abundant on the shores of the 

 mainland close by. On 21st February 1912, 38 males and 6 females were 

 collected at Wangi, and on the following day 129 males and 8 females on another 

 part of the shore near by. The whole of these were taken on the actual shore, 

 the vast majority of them drinking at damp sand between tide-marks. They 

 were most abundant where there were mangroves, and it seems almost certain 

 that this species must breed in salt water, since the only fresh water in the 

 neighbourhood was in deep artificial wells. I am not aware of an instance of 

 anyone having been bitten by one of these flies on this occasion, but it will 

 be seen that the females were relatively very scarce, and as I have explained 

 elsewhere, in other Tabanidae under similar conditions the females are very 

 little inclined to bite. 



The eyes of both sexes are of a rather translucent greyish-green colour, and 

 the male eye has no area of large facets above. 



Genus Rhinomyza, Wied. 



The flies of this genus seem to be seldom found in very large numbers. They 

 usually frequent damp, well-wooded localities near water. From a limited 

 experience, they certainly appear to be largely crepuscular in their habits, 

 especially as regards their time of feeding. 



So far as I am aware, the eyes are always unicolorous, and in the male the 

 head is holoptic, the eyes being large, unhanded, and with clearly marked upper 

 and lower portions of large and small facets respectively. 



Rhinomyza perpulcra, Aust. 



This species is represented in my own collection only by a single female taken 

 on the Yala River, South Kavirondo, British East Africa, in May 1911, but 

 it appears to be not uncommon at certain seasons in Uganda, in well forested 

 localities. The above-mentioned specimen was biting a native soon after sunrise. 



