56 



also numerous at much lower elevations, e.g., the forested portions of 

 the Semliki Valley at under 2,500 ft." According to Dr. H. L. Duke, 

 in Western Uganda G. jusca preys to a considerable extent upon the 

 hippopotamus. 



In the North Katanga district of Belgian Congo, according to Dr. 

 Schwetz (132), G. fusca is restricted to forest, and usually, though not 

 always, to the vicinity of water. Like G. brevipalpis and G. pallidipes, 

 whether at rest or on the wing it prefers and is found almost exclusively 

 along roads and paths. Again, like the other two species mentioned, 

 it spends the day, or at any rate the greater part of it, sitting motionless 

 on the trunks or branches of trees, or on creepers, the resting attitude, 

 as in the case of G. brevipalpis, being head downwards. G. jusca is 

 stated by Dr. Schwetz not to occur in swarms like G. brevipalpis, 

 although where it exists it is often present in numbers. It is a more 

 bloodthirsty species than G. brevipalpis, and much more silent on the 

 wing ; although it often tries to bite at any hour of the day, the night 

 is its real period of activity, and the time when it is most lively is 

 about two hours after sunset. 



Glossina Juscipleuris, Austen. Beyond the fact that the type was 

 found in the Ituri Forest, North-Eastern Belgian Congo, and that it 

 has been taken in forests in Uganda by both Dr. R. Van Someren and 

 Dr. S. A. Neave (see p. 18), little or nothing is yet known as to the 

 biology and habitat of this species, which, as we have already remarked, 

 appears to be very widely distributed, though by no means common. 

 Glossina nigrofusca, Newst. Of this Tsetse-fly, again, we know 

 practically nothing. According to Austen, in Ashanti Dr. W. M. 

 Graham met with a specimen in a bush path. Austen adds that 

 G. nigrofusca " sometimes enters houses and will even attack the 

 inmates," appearing "to settle by preference on the legs." 



Glossina tabanijormis, Westw. Not much more can be said under 

 the present heading in the case of this species. In February 1917, and 

 in March of the following year, three specimens of G. tabaniformis 

 all males were taken by Dr. Schwetz (132) and his fly-boys in North 

 Katanga, Belgian Congo, in a narrow strip of forest some twenty yards 

 in breadth on the Buitshi stream, between the Rivers Lomami and 

 Sankuru (Long. 24-25 E., Lat. about 5S.). In each instance the 

 insect was resting head downwards on a tree-trunk ; of the two 

 specimens captured 20-23.iii.1918, one was caught about 5 ft. from 

 the ground shortly after sunrise, and the other in the same position at 

 sunset on the following day. 



Glossina brevipalpis, Newst. In his resume of what had been 

 recorded as to the bionomics of this Tsetse-fly down to 1911, Austen 

 writes : " In view of the possibility that G. brevipalpis may ere long 

 be proved to be a carrier of human trypanosomiasis, and the fact that 

 in the German East African littoral, at any rate, it is stated to be the 

 chief disseminator of Tsetse-fly disease among domestic animals, 1 

 special importance attaches to a knowledge of the present species. 

 Although many important details have doubtless still to be recorded, 



1 Dr. S. A. Neave (103), however, writing on G. brevipalpis a year later remarks : 

 ' The evidence as to whether this species is a carrier of trypanosomiasis is at 

 present very conflicting. It must be remembered that it frequently occurs 

 in company with G. pallidipes on the east coast of Africa, or with G. morsitans 

 in Nyasaland and Northern Rhodesia. On the other hand, where it is the only 

 known species of Glossina, as in the country to the north and north-west of Lake 

 Nyasa, which is full of cattle, there is no definite evidence of trypanosomiasis 

 among the stock." 



