14 



Principe only during the last twenty to thirty years. There appears 

 reason to suppose that Glossina palpalis, or the " Gaboon fly " as it is 

 called locally, must have been introduced with the cattle from the 

 African coast, and probably from the Gaboon, somewhere about 1820. 

 Up to 1890 the bite of the fly was regarded as harmless, and cases of 

 sleeping sickness were very rare. So long as the labourers drawn 

 from Angola were not numerous the number of cases was insignificant, 

 but when, in 1893 and 1894, labourers imported from Angola came 

 chiefly from the vicinity of Casengo, where the disease had attained 

 an enormous development, the malady began to spread with alarming 

 rapidity throughout the island. In 1907 the disease had assumed 

 such grave proportions that the Government appointed a Commission, 

 which spent a year in carrying out experiments, and suggested remedies, 

 but they were not legally enforced until April 1911. The author says 

 that up to August 1912, little or nothing had been done to carry these 

 measures into effect, and that when he arrived with others on a special 

 mission at that time great obstacles had to be contended with. It 

 required eight months' exertion before the prophylactic measures 

 suggested were at all properly carried out, and these have given results 

 beyond expectation. The author then proceeds to give an account 

 of the work done by the Medical Mission, of which he was the head, 

 in the ten months between August 1912 and the end of May 1913. 

 The island was divided into three zones, and one doctor appointed 

 to each, with the object of carefully studying each individual estate, 

 examining the blood of men and animals, and segregating those found 

 to be afiected. It may here be remarked that the gravest defect in the 

 report is the absence of sketch maps, which renders it difficult to 

 follow the very interesting details given. During these ten months, 

 out of a total population of about 5,000, the blood of nearly 4,000 

 persons was examined ; trypanosomes were found in 125 cases, 

 filaria in 454, and malarial parasites in 286. The percentage of all 

 cases of sleeping sickness found by the Mission in the island is given 

 at 7 "2 per cent., of fresh cases 3"1 per cent. ; this shows a marked 

 reduction as compared with 1908, when the percentage was 23 '5. 

 The total number of persons now affected is 361, of w^hom 50 present 

 every appearance of being cured. Of the persons examined, the per- 

 centages affected by filariasis and malaria were ITS and 7*1 respectively, 

 which figures indicate a marked reduction in these diseases also. Of 

 198 animals examined, 39 were found to be infected with trypanosomes 

 and two with filaria. The author states that in 1908, when a member 

 of the original Commission, he was of opinion that the native population 

 was inclined to disappear. It was calculated that the approximate 

 number of indigenous natives in 1900 was 800, whereas in 1908 it was 

 reduced to about 300, but the number has now increased, as 550 persons 

 were examined by the Commission. Fourteen pages of the report are 

 devoted to the question of the value of atoxyl as a remedy for animals, 

 and the author concludes from the observations made that the 

 drug has no value for this purpose, but that it merely acts 

 as a tonic, and so prolongs the life of the animal, and strongly 

 recommends that all infected animals should be killed as soon as the 

 existence of the parasite is verified. Thirty-two pages are devoted 

 to observations upon the work of prophylaxis carried out by the planters 

 against the spread of sleeping sickness The author says that he is 



