236 
Anopheles in Flanders 
TECHNIQUE AND METHODS. 
The apparatus employed for dipping was the top of an infantry mess-tin, 
the inside of which was painted white to facilitate detection of the larvae. 
The handle was lashed to a stick about 3 feet long in such a way that the tin 
could be manoeuvred into three positions (1) in the same straight line as the 
stick, (2) at an angle of 45° or (3) at right angles. With the co-operation of 
Lance-Corporal Hicks, 71st Sanitary Section, a more perfected little device 
was made and is here illustrated. 
Fig. 1. Diagrams illustrating the device used in collecting larvae from water. 
The strip of tin was tacked around the flat wooden handle so that a slot was formed for the 
insertion of the mess-tin handle. Ity altering the position of the mess-tin handle in the slot the 
device could be used rigid in the three different positions indicated. 
The position of the dipper could be altered at convenience according to 
the character of the vegetation and banks of the water under examination, 
the third position being useful when skimming and to obtain specimens well 
away from the margin, and the second when the banks of the breeding water 
were high. Anopheline larvae were obtained by merely lowering the dipper 
into a pool or by scooping up the water but many methods had to be em¬ 
ployed. It happened not infrequently that, while repeated scooping yielded 
no result, long skimmings of the surface among the vegetation were successful. 
In certain cases, when other methods failed, skimming the fringes of algae 
proved successful as did dippings taken at greater depths than the superficial 
two inches or thereabouts. No note in the negative was made in regard to 
a pool which looked at all promising for Anophelines till about 20 dippings 
proved fruitless. 
Observations were recorded in a notebook on the spot. 
THE ANOPHELINE CONDITIONS IN VARIOUS DISTRICTS. 
The area bounded by imaginary lines joining the most outlying places 
visited, viz. Millam, Wylder, Woesten, Ypres, Kemmel, Armentieres, Arques 
and Moulle, is approximately 350 square miles, but the area examined with 
varying thoroughness by all workers amounted to about 120 square miles 
only. Most of the districts of the complete area, however, have been touched 
and those described may be regarded as representative. Areas densely popu- 
