Distribution of Tropical Diseases in Africa. 431 
disease being extremely common, especially in the towns. 
Diphtheria and croup are also widely prevalent, being 15 per 
1000; diarrheea and gastro-intestinal disorders rather over 29 
per 1000. Dysentery also is very prevalent, especially in the 
district of Oran, where it is said to be due to the special 
character of the water. Small-pox and measles are to 
be found in Algeria, and both acute and chronic bronchitis 
and pneumonia are very frequently met with. This is con- 
trary to what one might have expected. With regard to 
phthisis, the death-rate is high, but this is only in the towns, 
and is caused by the number of phthisical patients sent to 
Algeria in the hope of cure. It is a great mistake for 
patients in whom phthisis has become well-developed to 
be sent to Algeria, for, although the climate is exceedingly 
good for those in whom the disease is either threatening or is 
in a very early stage, it is undoubtedly prejudicial to those 
in whom it has taken firm hold. Leprosy and oriental boil 
are extremely common, and so is hepatitis, both the acute 
and chronic varieties, and tropical abscess of the liver 
(especially in Oran). Syphilis and acute rheumatism do 
not occur nearly so frequently as in Morocco. Goitre is 
prevalent in the mountainous regions. Malaria is very 
prevalent in Algeria, although it is not so frequently met 
with as formerly, for sanitary science is beginning to make 
itself felt and to diminish its occurrence. It is not so 
frequently seen in the province of Algiers itself, as it 
is in those of Oran and Constantin, in which districts it is . 
about twice as prevalent. The amount of fever is unequally 
distributed throughout the year; the maximum amount 
occurs in the autumn, the minimum between December 
and May. July and October appear to be the two months 
when fever is most prevalent. Undoubtedly the heavy rain- 
fall from November to February diminishes the fever. On 
the whole the fevers are most prevalent in marshy areas with 
a sub-soil of clay, but, as Colin points out, there are localities 
infested by malarious fevers which are far from being marshy. 
But this forms one of the peculiarities with regard to malaria, 
and, as I shall point out elsewhere, is, I believe, due to the 
height of the ground-water. Probably the most malarious 
VOL. XII. 2F 
