316 MR. S. A. NEAA^E — REPORT ON A JOURNEY 



recorded above as near T. rotJischildi. These all frequented in considerable 

 numbers the water-holes at native villages and frequently bit the natives, the 

 last-named being apparently much the most bloodthirsty. 



Amongst the biting organisms in native huts, on the other hand, Clino- 

 CORID^ and floor-maggots, but not 0. moulata, are practically ubiquitous. 

 On tlie whole, the balance of evidence, in the present state of our knowledge, 

 would seein to be slightly in favour of one of these being the carriers of the 

 disease. 



The remarkable virulence and rapid course run by the disease in the 

 Luangwa Yalley cases is also worthy of note. Of the three Nyamadzi cases 

 two are already dead, while of the seven Petauke ones three are dead and two 

 more were in the last stage when I visited them some ten days ago ; and this 

 in spite of the fact that most of them denied feeling ill at all last April. The 

 same is to be said, I understand, of many of the Nyasaland cases. It would 

 appear, therefore, that we have here to face a particularly virulent strain of 

 the disease, perhaps connected with the method of infection ; or there is the 

 possibility that a distinct Trypanosome, with an entirely new carrier, is the 

 cause of these cases *. 



There can be no doubt that there is most urgent need of a properly 

 equipped Commission to make the necessary experiments and settle this 

 point, not only in Rhodesia, but also in Nyasaland, w^here the problem 

 appears to be identical. At present, the nature of the danger being uncertain, 

 the authorities are practically helpless to combat it. 



In conclusion I have to express my deep indebtedness to His Honour, the 

 Acting Administrator of North-Eastern Rhodesia, and the officials generally 

 of the British South Africa Company, who have rendered me every possible 

 assistance. 



Fort Jameson, 

 th-Eastern Rho( 

 October 3rd, 1910. 



North-Eastern Rhodesia, 



[With regard to the distribution of Glossina morsitans shown on the 

 accompanying map, it should be remembered that this includes only 

 Mr. Neave^s observations on his recent journey. Kinghorn and Montgomery 

 make the general statement that it would be difficult to find a continuous 

 area of fifty square miles free from fly anywhere in North-Eastern Rhodesia, 

 except in the following localities : — the Serenji plateau, the neighbourhood of 

 Fort Jameson, and on the high plateau between Lakes Nyasa and Tanganyika. 



* [It is possible that the disease may be due to Trypanosoma rhodesiense, which has 

 recently been described by Stephens and Fantham (Proc. Royal Soc. 1910, B. 561, pp. 28-32) 

 from the blood of a European who had been in the Luangwa Yalley. — Ed.] 



