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



except in bright sunshine, and though always more vigorous in the sun, I should 

 doubt if they can stand very long exposure to its direct rays. Damp cloth 

 stretched on the ground would appear to provide a suitable medium for absorbing 

 moisture, but it also seems to afford some attraction even when dry. 



With regard to the insect enemies of Tabanidae in the imago state, there can be 

 little doubt, I think, that they are preyed upon to a considerable extent by both 

 predaceous Hymenoptera and Diptera. Though there has not been time to work 

 out the details, the collections made on my last tour include two examples of Asilid 

 flies preying upon Tabanus and no less than nineteen on Haematopota, these Asilids 

 representing some eight or nine species. Several of the Haematopota were males. 

 The most important Hymenopterous foes of Tabanidae in Africa, as else- 

 where, are probably the fossorial wasps of the genus Bembex, though my collec- 

 tion contains only a single example of an attack by these insects, viz. : — Bembex 

 capensis, Lep., preying on Holcoceria nobilia, Griinb. I have very little doubt 

 that prolonged observation in suitable localities and at the right season would 

 produce numerous instances. The attacks of the Bembex would seem to be 

 most usually made when the Tabanid is itself attacking domestic animals, and 

 from the nature of the circumstances only females would be carried off on such 

 occasions. The Tabanids seem to be aware of the presence of these wasps 

 and of the risks they run, for I have noticed in these circumstances that they 

 will settle on cattle only under the belly or between the fore-legs, where it is 

 difficult for the wasps to seize them. 



This family is divided into two subfamilies. The first of these the Pango- 

 niinae is distinguished from the Tabaninae by the presence of spurs on the tip 

 of the hind tibia, and contains a number of rather heterogeneous genera. Two 

 of these, Chrysops and Rhinomyza, resemble the Tabaninae in their appearance 

 and largely in their habits. The males of these two genera also resemble those 

 of the Tabaninae in having in their eyes two distinct areas of large and small 

 facets. The other genera of the Pangoniinae, such as Pangonia (sens, lat.), 

 Silvius, Aegophagamyia, etc., have unicolorous eyes, with the facets all of one 

 size in both sexes and (except Silvius) the head is not completely holoptic, the 

 eyes only meeting in the middle line on the vertex. 



The Tabaninae include the two larger genera Tabanus and Haematopota, as 

 well as Holcoceria, Griinb., represented, so far as our present knowledge goes, 

 by a single species. One species of the West African genus Hippocentrum, 

 Aust., also comes into the region under discussion, a few specimens of H. versi- 

 color, Aust., having been recorded from the forested areas in Western Uganda. 



Genus Cadicera, Macq. 

 Cadicera speciosa, Aust, 



My experience of flies belonging to this genus is confined to the above species 

 of which I took four females in rather densely wooded country at the foot of 

 Mt. Kifulufulu on the Iringa-Kilossa road, German East Africa, in December 

 1910. They were all taken biting native cattle, except one, which entered my 

 tent, but did not attempt to bite. This capture extends the hitherto known range 

 of the genus very much further north. 



