468 
NOTES ON THE PREVALENCE OP 
The Arab and African — for the class of native admitted — 
fighting-men, followers, and carriers, cannot be regarded as 
abnormally high when compared with work done elsewhere 
on institutional and village infection under similar sanitary 
or climatic conditions, or both. African troops, police, and 
domestic servants, suffer far less from helminthic invasion 
than the villager, whose infection is due to promiscuous defeca- 
tion in any patch of scrub he finds convenient. This habit is 
universal, and, probably, more than any other factor, accounts 
for the wide-spread distribution of ankylostomiasis. It is not 
in any way unlikely that in this manner the feces of one or 
two infected individuals may, in a very short time, be the 
cause of the infection of the inhabitants of a whole village 
or series of villages. 
Some points with reference to the ages of those suffering 
from ankylostomiasis may be of interest. Children and young 
adults, unless heavily infected or suffering from some inter- 
current disease, do not apply for treatment as frequently as 
one might suppose. Of this type, those who do so, do not, 
as a rule, refer their symptoms to any particular system, but 
give vague histories of not feeling well or of vertigo ; and, in 
the case of police askari, usually approach one with the idea 
of obtaining a change or transfer to stations in their own 
native districts : the reasons advanced being that the local 
food, water, salt breezes, or want of them — dependent on the 
area in which they are at the time of serving — have in some 
abstruse manner seriously affected their health. 
These also frequently develop mental symptoms, taking 
the form of home sickness, melancholia, and delusional 
insanity. In all such instances the faeces should always be 
examined. 
The adult coast-native possesses, as a rule, a full knowledge 
of the disease, and when applying for treatment states that he 
is suffering from ankylostomiasis, or sajura , as he calls it, 
and the clinical picture is usually characteristic. 
Ankylostomiasis is not uncommonly a terminal infection 
in the aged. 
The first table, immediately below, gives details of the 
different causal parasites observed. The other two tables 
