12 
Failure to 
find the 
breeding- 
place of the 
Anopheles at 
Wilberforce: 
its probable 
situation. 
Although Major Ross was of the opinion that the breeding- 
place would eventually be found in close proximity to the 
barracks, since it was improbable that the female mosquitoes, 
which are not impregnated until they have enjoyed a meal of 
blood, would have to fly far in order to deposit their eggs, we 
made a search down the hill side in the direction of mangrove 
swamps fringing an arm of the sea known as Aberdeen Creek. 
The side of the hill below the barracks is covered with bush, 
and owing to the nature of the ground it was found impossible 
to get quite as far as the mangrove swamps by this route. At a 
distance of about a mile below the barracks, however, a level 
tract of marshy soil was met with. Here the ground was open 
and overgrown with grass ; the soil was nearly everywhere 
covered with water, though seldom more than an inch in depth, 
stagnant or nearly so in some places, gently flowing in others, 
At intervals small pools were found, but a careful search by five 
people failed to disclose any mosquito larvae whatever. A sub- 
sequent visit to the adjoining mangrove swamp itself produced a 
like result, which was not surprising, since the ground was 
alternately submerged and left nearly dry by every tide. 
Although the locality of the breeding-place of the Wilberforce 
Anopheles remained an enigma up to the time of our departure 
from Freetown, there is little doubt but that it will eventually 
be found, if at all, in or on the edge of the village itself. At the 
time of our visit the officers of the 3rd West India Regiment 
were quartered in houses in the village, where, in at least one 
case, they suffered from the attacks of Anopheles quite as much 
as did the men in barracks ; it may be added that several of 
the officers were attacked with fever during our stay. It is 
probable that the trees clothing the sides of the hill on which 
Wilberforce stands would intercept any mosquitoes either flying 
or blown towards the village from a distance ; and, as already 
hinted, a female mosquito must return to a suitable accumulation 
of water — probably to the place where she herself was hatched — 
in order to lay her eggs. The streets and roads in and about the 
village of Wilberforce, in striking contrast to so many of those 
in Freetown, are singularly free from puddles, and in the course 
of many visits I did not succeed in discovering more than four, 
all of which were tenanted by Culex larvae alone. The precincts 
of the houses were also searched to no purpose. P>ut it was 
