70 
PROPHYLAXIS OF MALARIA. 
place of scores and even hundreds of anophelines which were en¬ 
deavoring to get within the buildings, and it was possible to kill 
hundreds of these insects in this situation almost every evening during 
the rainy season. 
Mosquito traps have also been used extensively in the Canal Zone, 
and Orenstein describes one devised by Sanitary Inspector Bath, 
which has proved satisfactory. It consists of a half-cylinder con¬ 
structed of wire netting, having two ridges inside it, “ the apices of 
which are perforated by longitudinal slits about J inch wide and 3 
inches long. Through the slits in these ridges the mosquitoes enter 
the chamber of the trap, and can not, for some reason, find their way 
out again.” 
The traps are so placed as to catch the mosquitoes either when en¬ 
tering or leaving a building, and in the Canal Zone it was found that 
more anophelines were caught if the traps were placed on the lee of 
buildings, while more culicines were captured if the traps were in¬ 
stalled on the windward side of the buildings. 
Regarding the value of catching mosquitoes Orenstein well says 
that: 
When it is remembered that in malaria a period of at least a week must 
elapse before the mosquito which has fed on an infected person can transmit 
the infection to another person, and when it is recalled that an anopheline 
filled with blood becomes sluggish and does not fly very far for some time, the 
efficacy of killing mosquitoes within habitations becomes self-evident. 
And he concludes that u catching mosquitoes by hand within dwell¬ 
ings is a measure of great value in the prophylaxis of malaria. It is 
especially applicable to temporary camps.” 
It is obvious that this prophylactic method might be of the very 
greatest value to the military service in the case of camps in malarial 
localities and it could be so easily put in operation that its neglect 
would be inexcusable. All that would be necessary would be to detail 
a certain number of men for the purpose, under an intelligent non¬ 
commissioned officer, the camp being districted for the purpose. No 
great amount of training is necessary, as mosquitoes are easily recog¬ 
nized and the method of handling the killing tube and u swatter ” is 
quickly acquired even by the most unintelligent laborer, as shown 
by the fact that all the work in this line in the Canal Zone was done 
by the West Indian negro. In the field where troops are in tents 
for some time, as at maneuvers or in more or less permanent camps, 
and where mosquitoes are prevalent, this method is certainly deserv¬ 
ing of the most thorough trial. 
In barracks and quarters in posts situated in the Tropics mosquito 
catching would also be a valuable method of prophylaxis and could 
be accomplished by native help at a comparatively small expense. 
In many posts in the Philippines, where it has been found impossible 
