THE MIGRATORY HABIT OF HOUSEFLY LARVAE. 
ment differed from the first was in the fact that the manure in the 
container was not sprinkled with water at any time, except for a 
light shower on September 19 and another on September 22. Much 
of this rainfall failed to reach the manure in the container because of 
the covering of the cage. A comparison of the results of this experi- 
ment with those of the first indicate the importance of moisture as a 
stimulus. 
Table II. — Migratory habit of housefly larvze; Experiment No. 2. 
Date. 
Larvae 
collected 
from pan. 
Flies 
caught 
in traps. 
Date. 
Larvae 
collected 
from pan. 
Flies 
caught 
in traps. 
1913 
Sept. 17 
18 
19 
21 
22 
23 
24 
27 
28 
29 
15 
132 
168 
894 
427 
35 

1913 
Sept, 30 
Oct. 1 
2 
3 
4 
6 
7 
8 
64 
80 
125 
52 
78 
84 
44 
22 
43 
43 
33 

1,671 
668 
Allowing for the few larvse and adults which may have escaped, 
the totals may be given in round numbers as 1,700 larvse and 700 
adults. Thus from a possible total of 2,400, 1,700, or about 71 
per cent, were destroyed. In passing it is unnecessary to point out that 
here 700 flies did pupate in the manure in spite of the fact that they 
had every opportunity to leave it. 
With the approach of cold weather the work against the housefly 
was transferred to the experiment station at Audubon Park, New 
Orleans, La. Some other experiments of a similar nature were car- 
ried out here with smaller containers and cages. The strong wire 
baskets of the kind commonly seen in markets and stores for the 
display of fruits and vegetables made first-rate "maggot traps." 
The baskets used were 16 inches in diameter and 16 inches high 
and stood on legs 9 inches high. A galvanized-iron pan 2 feet square 
was made for this to stand in, and over all this was placed a cage 
consisting of a light wooden framework covered with black cloth. 
The top of the cage was covered by boards in which was an opening 
for the attachment of flytraps. 
The third experiment was started on November 13. The basket 
was filled with manure taken from stables on November 12. The 
manure, which contained very little straw or bedding of any kind, 
was packed firmly in the basket and sprinkled with 4 quarts of water. 
The iron pan below was partly filled with water. The cage with its 
traps was not put in place until November 18, thus exposing the 
manure to possible infestation for a period of five days. The manure 
was sprinkled daily as long as larvas appeared. 
