TSETSE-FLIES OF THE KABALO-ALBERTVILLE RAILWAY. I 73 



scientific journals). In other words, if, after having examined several spots of the 

 first or third sections, and having found one or other species of Glossina there, one 

 may conclude with almost certainty that the same species are to be found throughout 

 each section, it is different in the second section, where various species may be found 

 at a few kilometres distance from each other. So that in making an approximately 

 accurate map (none could be absolutely correct) of the distribution of Glossimi in the 

 second section, the ground must be examined almost step by step. 



The districts on the second section where I have spent a day or two seeking Gloss ina 

 are as follows :■ — 



(1). Km. 169 (Hospital). A fine plateau, about 3 km. (in a straight line) from the 

 Niemba and 1*500 km. from the Lukuga. Vegetation transitorily wooded (especially 

 artificially), but park-like around the Hospital. Apart from the palpalis found at 

 the Lukuga and the Niemba, no Glossina were seen about the Hospital. Above all, 

 the absence of brevipalpis astonished me. The Director of the Hospital informed 

 me that this species existed about the Hospital, but in very small numbers. During 

 my stay at km. 169, it first rained and then turned cold. 



(2). Km. 123. The railway here passes beside a deep, marshy valley, the source 

 of a stream which is a tributary of the Loyeye. The swamp is covered with a very 

 thick growth of trees forming quite a forest. The rest of the surrounding district is 

 covered with transitory vegetation (forest-park, etc.). G. brevipalpis captured in 

 the evening, on the railway ; no other species found. 



(3). Km. 105. About 2 km. from the source of a stream, tributary of the Loyeye. 

 The source is surrounded by true forest ; about the railway in this district the vege- 

 tation is mixed and transitory (forest-park). On the railway, close to the plate- 

 layer's house and between the railway and the source, I caught several pallidipes, 

 numerous brevipalpis, two palpalis (probably coming from the source), and two 

 hisca. 



(4). Km. 93. Stream Luambashi. The country is here flat and relatively little 

 wooded ; Borassus palms are present. I captured several palpalis at the stream 

 close beside the railroad ; no other species was found. 



The results show that in none of these four places have I seen morsitans, which 

 hardly surprises me. But what does astonish me is the absence of morsitans between 

 Luizi and km. 93, the vegetation along all this distance being continuously park- 

 like. It is true that I did not stop here, and it is therefore possible that morsitans 

 may occur here, although certainly rare. But it is also possible that the park only 

 exists in the vicinitv of the railway, and that further off at one or both sides the 

 vegetation is different. All this must be examined again. 



Another district we investigated carefully is the route between km. 131 and 138. 

 This forms a continuous strip of forest and it is probable that fu sea, among other 

 species, will be found there. With regard to the Luizi, the banks of which are com- 

 pletely cleared of trees, both up and down the railway, I saw no palpalis during my 

 two journeys and short stoppages. However, I was assured that palpalis is sometimes 

 seen close to the bridge over the Luizi. This is possible, especially as the banks of the 

 Luizi about 1 km. down the river become wooded, and it is probably from there that 

 this flv comes. 



