MALARIA EXPEDITION TO THE GAMBIA 
J 7 
Presence of the Malaria Parasite in its Definitive Host 
Mosquitoes of the Anopheles genus were collected for examination from 
the soldiers' quarters and brought to me by an orderly from time to time in small 
batches ; these were kept from one to three days, to allow of the digestion of the last 
meal of blood, and then dissected. Out of twenty-seven complete dissections, three 
mosquitoes were found infected ; two of these had zygotes in the stomach wall, three 
in one and two in the other, from six to ten days old, variety undetermined. In the 
other infected mosquito, sporozoids were found in the salivary glands, principally in the 
middle lobes. Out of a dozen mosquitoes {Anopheles) caught in the hospital, chiefly 
irom the West Indian soldiers' ward, two were infected. A few zygotes about three 
days old were found in the stomach in both cases, and were identified as Haemamoeba 
malariae ; these two mosquitoes were caught in the dispenser's (native) net three 
days previously. An examination of his blood was made, but no parasites were 
detected ; he had previously had no symptoms of malaria. It is very probable that 
these mosquitoes were infected in the town, and not from the soldiers in the barracks 
or hospital. To obtain Anopheles from these places it was necessary to visit the 
barracks just as dawn appeared, 6 a.m., when they were found on the walls, just 
over the beds of each soldier ; during the day I was never able to detect an Anopheles 
mosquito in this room ; they were probably all driven out by the disturbance of 
rolling up kit, etc., in the morning. The Anopheles examined were all Anopheles 
costalis, except three Anopheles pharoensis, which were negative. 
At the Cape the natives brought me a good number of mosquitoes collected 
from their huts ; nearly all collected in this way were of the Anopheles genera, includ- 
ing Anopheles costalis and Anopheles funestus, the number of the latter greatly 
predominating. 
Twenty-four complete dissections were made, two Anopheles funestus being 
found infected ; in one the salivary gland contained sporozoids in large quantities, and 
in the other four medium-sized zygotes with three empty capsules were present on 
the stomach wall. Unfortunately, many mosquitoes brought back to Bathurst had 
died on the way, and were unfit for dissection on arrival. 
Other Haemamoebae. — The nature of the expedition did not permit of any 
extensive investigation on the distribution of other Haemamoebidae in the Gambia, 
still a few animals were examined. 
The common yellow and green African canary was universally infected with 
Haemamoeba danilewskii (Halteridium) ; some tame pigeons from the various factories 
also showed this parasite in their blood, and also a few birds shot in the bush. 
Haemamoeba relicta (Prateosoma) was never found ; but the number of birds 
examined was not sufficient to form an opinion as to the absence of this parasite 
from the Gambia. 
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