18 
survey of Black Swamp Bayou, on Lake Bolivar plantation, and 
Gin Bayou, on Nugent plantation. On the former location an ideal 
habitat was afforded among trees and floatage carelessly thrown into 
the stream. Many larvae, one-half to nearly full grown, were col¬ 
lected on this day and only one pupa was seen. On May 15 this 
pupa emerged in the laboratory as a specimen of a male A. quadrimor 
eulatus. 
A moderate number of water containers used as traps, distributed 
throughout several plantations, were utilized in an endeavor to learn 
the time of initial egg laying and hatching. These were selected, 
primarily, either for the reason that larvae had been observed in 
them in the previous fall and winter or because they were located in 
advantageous places. The containers were usually stationary vessels, 
some of which were filled with water, which was allowed to stand 
undisturbed; in others the water was replenished when necessary. 
They consisted of wooden water barrels, old boats or canoes serving 
as water troughs, old wooden drinking troughs full of rain water, 
iron cisterns, cement water troughs, fire buckets and barrels, and 
numerous ground cisterns. At least one of these was located on each 
of the various plantations and inspected regularly at intervals of 
from three to four days during th£ months of February, March, and 
April, when evidences of mosquitoes were absent from natural water¬ 
courses. 
None of these produced eggs or larvae until May 25, when, for the 
first time in this region, two large water barrels were found infested. 
One barrel contained 30-40 larvae, 1 to a few days old, and the 
other harbored older larvae to the extent of 20-25 specimens. It 
appears that container infestation generally follows propagation in 
watercourses. In two instances at least was this observed; one in 
which an old boat alongside a muddy ditch was not infested until 
two weeks following the appearance of full grown larvae in the latter, 
and another in which wooden barrels kept on a house gallery 25 
meters from a flowing stream did not harbor larvae until 11 days 
following the infestation of the watercourse. 
The finding of Anopheles eggs in streams under natural environ¬ 
ments is conceded to be a difficult task, even when mosquito propaga¬ 
tion is at its maximum, but the difficulties are manifold when at¬ 
tempting to locate these tiny objects during the winter period. The 
effort met with uniform failure, though, allowing for human limita¬ 
tion, Anopheles eggs may have been overlooked in the present studies. 
As a partial control to this condition, experiments were conducted in 
the laboratory, apart from the hibernation investigation, during 
August 20 to October 15, 1915, to determine at what temperature 
Anopheles lay eggs and the nature of temperature requirements for 
their hatching. 
