ii8 I gave each of them a large dose of citrated blood from the sick mule neither developed any infection.

Under these circumstances, I am unable to express any opinion as to the species which this trypanosome represents. The curve, Chart II, is certainly rather peculiar, there being two apices. It may be that a sufficient number of trypanosomes has not been measured, or, again, it is possible that had the fixation been better the staining of the free flagella might have been better also, and the two apices might then have been compounded into a single apex at or about 19/i. Even in this case, however, it would not have answered very closely to that given by Bruce for the Uganda strain of T. bnicei. I suggest that it may be the same pleomorphic trypanosome {Try-panosoma, sp. ?) found by Kinghorn and Yorke in a bushbuck. The mule transport had been working in the southern Bahr-el-Ghazal before coming to Western Mongalla, so that it is possible the infection was derived in the former province, where but little is yet known regarding the different strains of trypanosome affecting domestic animals. In the past there has been free communication between what was the Lado Enclave and both Uganda and the Belgian Congo, so that, in all probability, various trypanosome infections of bovines and equines have been introduced into Western Mongalla. It is very desirable, as has been shown by the work of Kinghorn and Yorke in many reports, notably those cited, " as also by Duke and by numerous French observers in West Africa, to determine accurately the different species of trypanosome affecting domestic stock and their insect vectors. These short and incomplete notes may be of some help to those whose duty it will be to work out the problems on the spot, for there is now a good laboratory at Yei, and Lieutenant Ranken intends to extend his researches, both to the disease in domestic animals and to the question of the presence of tr}'panosomes in big game. The region is so remote and difficult of access that it is well-nigh impossible to carry out the work satisfactorily in Khartoum.

II. In the British Medical Journal for July 6th, 191 2, I drew attention to the subject of tsetse fly traps. I have now had large traps constructed by the Andres Maire Company. These (PI. X, fig. 6) are not e.xactly what I intended. Indeed, the}' differ very