260 THE HOUSE FLY—DISEASE CARRIER 
from the seeds of sugar beets stored in a mill; also 
from larvae found with other larvae on the roots of roses, 
as well as from under the bark of a post-oak pole. Ex¬ 
act observations have been made here showing that the 
larva is undoubtedly carnivorous: it has been fed upon 
the larvae of stored grain insects, and when found in 
woolen goods and under carpets it is undoubtedly in 
search of clothes moths upon which to feed. 
The larva is long, white, and snake-like in shape, 
with a dark head. It apparently has many segments to 
the body, since each of the abdominal segments is di¬ 
vided by a strong constriction. In feed stores the flies 
are nearly always to be found around the windows, 
and the probability is very strong that they feed upon 
such small soft-bodied creatures as flour mites .and 
beetle larvae. 
Nothing definite has been ascertained concerning the 
duration of the different stages, but from larvae taken 
in January adults issued in April, and from larvae re¬ 
ceived April 18th adults issued on the 9th of June; 
with larvae received August 6th, one changed to pupa 
on August 25th, another on August 29th, the flies issu¬ 
ing September 10th and 12th respectively. 
It is a pleasure to state that at least one of the flies 
found in houses is probably beneficial rather than in¬ 
jurious, and that this species is Scenopinns fenestralis. 
