292 APPENDICES 



water-side populations in Africa usually go even more 

 naked than others. 



It is obviously a desirable thing to avoid infected 

 areas, and, if possible, to prevent natives from inhabit- 

 ing them ; it is also desirable to prevent infected 

 natives from entering uninfected districts, but this 

 latter measure is beset with almost insuperable diffi- 

 culties. Even in civilized countries whose frontiers 

 are well defined and not easily crossed without detec- 

 tion, the establishment of S3^stems of quarantine has 

 been excessively difficult ; how much more so would 

 it be, therefore, in savage countries with ill-defined 

 boundaries, and where the number of officials com- 

 petent to enforce the regulations is necessarily very 

 small. It has been suggested that all natives showing 

 enlarged cervical glands should be isolated ; but this 

 would involve the detention of a certain number who 

 were not suffering from sleeping sickness, whilst a 

 still larger number would escape detection by reason 

 of the very insidious nature of the disease in its early 

 stages. 



The most recent recommendation is that of Professor 

 Koch, who asserts that in the neighbourhood of the 

 Victoria Nyanza the tsetse-flies subsist almost entirely 

 on the blood of crocodiles ; he therefore suggests the 

 extermination of these reptiles by the destruction of 

 their eggs. It is difficult to take this suggestion really 

 seriousl}^ The numbers of crocodiles are so immense, 

 their distribution is so wide, and their powers of repro- 

 duction so great, that it is doubtful whether the best- 

 conducted campaign against them would have any 

 appreciable effect. And it is only too probable 

 that, if they were deprived of crocodiles' blood, the 

 tsetse-flies would find some other food, as they un- 

 doubtedly must do in those districts — e.g., the shores 

 of Lake Ruisamba and the Albert Edward Nyanza — 



