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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 16 
size, its stage of development, and upon temperature conditions. Lar¬ 
vae feed but little during cool weather and usually stop feeding several 
days before pupating. Attempts made to rear larvae in nutrient agar, 
with the idea that they could be more easily kept under observation in 
this material, were unsuccessful. 
Larvae of Tabanus trimaculatus Pal. Beauv. have been taken several 
times in the field. Some were found in soft mud at the edge of and 
beneath the water of a pool which is stagnant for the greater part of the 
year, while others were dug from moist soil beside a brook. Larvae 
taken in November and December pupated in April and the adults 
issued in from 8 to 15 days after pupae were formed. 
Several larvae of Tabanus imitans Walk.have been taken from mud at 
the edge of a small pool. Taken on Novembers, 1922, these larvae lived 
in breeding jars from the first of December until the first of March 
without feeding and without increasing in size. They then resumed 
feeding on earthworms and grew rapidly until the first part of April, 
when they again stopped feeding and became inactive. They remained in 
this condition until June, when they pupated, and the adults issued 12 
or 13 days later. 
A single larva of Tabanus wiedemanni , O. S., was taken on March 11, 
1922, from mud under about ten inches of water in a swampy meadow. 
It pupated on April 30 and 13 days later the adult appeared. One 
larva of Tabanus reinwardtii and one of T. fuscopunctatus have also 
been collected in the field. The larva of the first named species was 
found in sand beside a slow flowing brook and that of the second species 
in the mud at the bottom of a brook. Both pupated in May; the adult 
of Tabanus reinwar dtii issuing on May 31 and that of Tabanus fusco¬ 
punctatus on June 11. 
Only two Chrysops larvae have been taken. Both were found early 
in March in mud under about a foot of water and about two feet from 
the bank of a small brook. On April 11 the two larvae pupated and 
after a period of 6 days adults emerged. One was a female of Chrysops 
callidus O. S. and the other a male of Chrysops flavidus Wied. 
Professor Hine has already recorded observations made in Louisiana 
which indicated that the immature stages of Tabanus annulatus Say 
occurred in rotten logs. We have taken many larvae and a number of 
pupae from well rotted logs. With the exception of a single specimen 
of Tabanus fulvulus Wied. no other species has been reared from larvae 
found in such material. Larvae found in rotten wood were kept in 
such material in the insectary and fed earthworms. The first pupa of 
