A. D. Peacock 
249 
Bryce, Murray, Reed, Sands and Lieutenant Regan. Specimens and informa¬ 
tion were received from Captains Bain, Rankin, Johnstone, Armitage, 
R.A.M.C. and Lieutenants MacDonald and Saltmarsh, R.A.M.C. (T.F.) 
(London Sanitary Coy.). The assistant surveyors who performed so much 
intelligent work were Corporal Barnes, Lance-Corporals C. Roe, W. Roe and 
Gudger and Privates Hargreaves and Walden all of the sanitary service. 
SUMMARY. 
(1) The object of the investigation was to ascertain the condition of the 
Second Army area of Southern Flanders in regard to Anopheline mosquitoes. 
(2) The data of this report have been derived from three sources (1) from 
the writer’s surveys during the summers of 1915 and 1916; (2) from the 
writer’s survey of September 1918; (3) from various collectors the bulk of 
whose specimens were collected during September 1918. 
(3) Circumstances determined that the method of investigation should 
deal almost exclusively with breeding waters. Except on a very small scale 
no attempt could be made to rear larvae and pupae or capture adults. 
(4) The distribution of a circular and pro-forma resulted in a certain amount 
of information being obtained from medical officers and officers commanding 
sanitary sections. Valuable assistance was also rendered by certain non¬ 
commissioned officers and men. 
(5) The surveyed area of the Second Army zone bounded, roughly, by 
imaginary lines joining the places Millam, Woesten, Ypres, Kemmel, Ar- 
mentieres, Arques and Moulle was about 350 square miles; most of its districts 
were touched upon, their areas totaling about 120 square miles; eight main 
districts and 12 isolated districts, representative of the country, were surveyed 
with varying thoroughness and skill; the main districts were the Advanced 
Zone, Poperinghe, Hazebrouck, Southern, Rubrouck, Central, Waterlands and 
Armentieres. 
(6) Out of 40 adult Anophelines, caught wild or reared from larvae and 
pupae, all proved maculipennis. 
(7) Twenty-three A. maculipennis, females, were caught in one afternoon 
in a dark, damp medical aid-post. 
(8) No seasonal preponderance of any one size of larvae was observed 
during September 1918. 
(9) Out of about 1233 records of sites inspected, 178 refer to Anopheline 
haunts, 5 referring to captures of adults. 
(10) Of the 173 Anopheline waters discovered 127 (73*4 %) were pools or 
lakes, 16 (9-25 %) were holes (shell-holes or pits), 12 (6*9 %) were running 
waters (9 streams, 3 canals), 8 (4*6 %) were ditches, 6 (3-5 %) were marsh, 
2 (1-2 %) were receptacles (1 a tin and 1 a concrete basin); 2 records give no 
details. 
(11) From 106 records the number of waters with few Anopheline larvae 
(up to about 10) was 67 (63-2 %), with numerous larvae (3 and more per dip) 
