145 



NOTES ON A FEW PHOTOGRAPHS ILLUSTRATING THE 

 HAUNTS AND HABITS OF GLOSSINA TACHINOIDES 

 IN BORNU, NORTHERN NIGERIA. 



By Dr. Bernard Moiser, W.A.M.S. 

 (Plates XIII— XVII.) 



During a residence of a little more than two years (two tours) in Bornu, 

 Northern Nigeria, I have investigated the haunts of tsetse-flies there, whenever 

 an opportunity has occurred, and I find that these flies (G. tachinoides is, so far 

 as I know, the only species occurring there, though one specimen of G. morsitans 

 was captured in one place) are confined to small patches of dense jungle situated 

 along: the course of small rivers. I have now come to know well the kind of 

 " bush " where I can expect to find the flies, and the places where it is useless to 

 look for them. They are found in quite localised areas, in close proximity to 

 rivers or marshes, where there is water all the year round, and where the ground 

 is covered with tall shady trees, mostly tamarinds, and thick undergrowth of 

 thorns and creepers, with some ebony trees. 



I do not mean to say that every patch of bush having these characters will be 

 found to harbour the flies, for I have examined many such places without finding 

 them. But the possibility that the ebony trees are in some way a factor de- 

 termining the presence of the flies has often forced itself on my attention, for they 

 are invariably to be found in the " baits," and I have never found the flies in any 

 locality devoid of them. It is true that these trees are not the only kind common 

 to all the belts, but, whilst engaged in discovering the natural resting place of the 

 flies, I noticed that they were most frequently seen resting on the under side of 

 small ebony shoots close to the ground. These ground shoots have small hori- 

 zontal branches, devoid of leaves except at the tip, and it is on the under side of 

 these horizontal twigs (as well as on little horizontal thorn twigs) that the flies 

 come to rest. Also, in one experiment, I observed a fly trying to insert its 

 proboscis between the bark and wood of a broken ebony twig. 



Two of the photographs (Plate xiii) show living specimens of G. tachinoides in 

 such a position of rest. These were obtained in a small " belt" at Bellaram, near 

 Geidam, previously described (Bull. Ent. Res. iii, 1912, p. 195), the characteristics 

 of Avhich are shown in the accompanying photographs. 



Another noticeable feature of all the belts I have examined is the large 

 number of warthogs to be found in and arouud them, but whether these animals 

 have anything to do with the occurrence of Glossina tachinoides, I cannot at 

 present say. 



In a future experiment, I intend to cut down the ebony trees only in a belt, 

 and see if this will affect the presence of the flies. A previous article described 

 {he. cit.) how the complete disappearance of the flies was brought about by clearing 

 the whole of the undergrowth, leaving the tall shady trees standing. 



