Distribution of Tropical Diseases in Africa. 453 
of the northern part of this area, except in the high region to 
the north-east of the Victoria Nyanza, where it is more 
common. Diseases of the chest are found throughout the 
whole region, but bronchitis is far more common than either 
pleurisy or pneumonia. A form of plague has visited 
Uganda on several occasions, and there are reports of it 
having occurred on the White Nile to the south of Lado and 
in the Bahr-el-Ghazel district, Guinea-worm is most pre- 
valent to the west of the Nile throughout the province of 
Rohl and Bahr-el-Ghazel. Round worms are also met with, 
and yaws is occasionally seen. Syphilis is widely spread in 
those districts where the slave trade has been carried on, but 
it is not prevalent in other regions. Leprosy is met with, 
but not extensively. Llephantiasis arabum occurs, especially 
on the west of the Nile to the south of Lado, Skin diseases 
are extremely frequent, except in Uganda, and boils are of 
common occurrence every where. 
With regard to nervous diseases, temporary insanity is 
often met with, but it is rare to see cases of permanent 
aberration. Mpilepsy is fairly common, and occurs chiefly in 
girls. 
Ophthalmia is comparatively frequent, although it is not 
nearly so prevalent as in Egypt. With regard to diarrhoea 
and dysentery, both diseases are met with throughout this 
region. They are more prevalent throughout the Nile valley 
and in the west than in Uganda and Unyoro. The so-called 
blackwater fever certainly occurs, and so does typho-nalarial 
fever, but in all cases I came to the conclusion that these 
were different varieties of remittent fever. 
Passing now to the Congo region of Equatorial Africa, we 
find that malaria is prevalent over the whole of the district, 
All varieties occur, from mild attacks of intermittent fever 
lasting three days, to the most pernicious forms of fever, such 
as are seen at Vivi and Stanley Pool. It is said that the 
mortality of Europeans in the Central Congo region is about 
25 per cent. Here, too, the so-called blackwater fever is 
common. There are no reports of enteric fever from the 
Congo, but typho-malarial fever is. reported. I believe, 
however, that it is really simple severe remittent fever with 
