2 1 8 
In the investigation considerable attention was paid to the analyses 
of the efflorescence or incrustation formed on the screening for the 
determination of the constituents involved in the corrosion. The 
specimens presenting the highest degrees of deterioration furnished 
the largest amounts of incrustation. The deterioration of the screen¬ 
ing is largely due to the presence of iron in the brass alloy, plus the 
influence of a hot, moist atmosphere. 
Observations continued over a period of four years on screening 
made of copper and zinc with a composition nearly: — 
Copper ... 84-92 
Zinc ... ... _ 
Iron . . 
89-94 
84-83 
88-59 
95*5 
— 
14-90 
— 
4 M 5 
— 
0-06 
0-04 
o-o 
showed that these resist the corroding actions of a hot, moist 
climate much better than screening made of brass with an average 
composition of : — 
Copper. 
Zinc ... . 
Ir ° n ..’ ... T +- 
a °d ^ * s concluded that screening intended for use in the tropics, 
exposed to heat and moisture, should have a high copper content, 
higher than brass, and he as free as possible from the presence of 
iron. 
VALl ^ 0F DAILY COLLECTION AND DESTRUCTION OF LIVE 
SQUITOS CAUGHT IN BARRACKS AND QUARTERS 
Abundant material was received for observations on the value 
* is P rac ^ ce - 1 he daily catcli of mosquitos from barracks of 
various districts would be sent alive to the laboratory. The 
squitos were transferred to breeding jars and fed on dates or 
until their intestinal tracts were free from blood. They 
ien killed and examined for zygotes or sporozoites. The 
P s examined were: Ce. albimana , Ce. tarsimaculata, Cl¬ 
ergy rot arsis, Arr. (?) malefactor , and A. pseudopunctifennis. A 
j . 10 specimens of Culicines were also examined at this time, 
k'lr n ° te ^ 0rthy * anc * s P e aks well for the practice of these daily 
, P’ * ' at k ut one naturally infected Anopheline was found, 
and that one a specimen of Ce. argyrotarsis. 
of tl tCr X 7 firSt fort - y ‘ tllree negative dissections no record was kept 
five hundre 1 nUm ^ er exarn ‘ ne< ^> but it was in the neighbourhood of 
