to the amount swallowed by the insect, as much as 100 ce. of 
blood may ooze from the puncture after the fly has left. Other 
important species include: the striped horse fly, 7. lineola Fab., 
T. costalis Wied., T. abactor Philip, T. quinquevittatus Wied., 
T. sulcifrons Macq., and T. nigrovittatus Macq. 
Deer flies belong to the genus Chrysops and are smaller than 
horse flies. They are active during the hottest weather and are 
often quite abundant during rainy spells. More than 60 species 
occur in eastern United States. Diachlorus ferrugatus (Fab.) is 
a common and notorious pest in swampy areas from New Jersey 
to Florida and Louisiana, especially in the Carolinas. 
FAMILY RHAGIONIDAE 
SNIPE FLIES 
Snipe flies are commonly found in the woods, especially in 
moist areas. The majority are brownish or gray; others are black 
with spots or stripes of white, yellow or green. Both the adults 
and larvae feed on other insects. Adults of the genus Symphoro- 
myta fly persistently about the head and are very annoying be- 
cause their bites are painful. 
FAMILY ASILIDAE 
ROBBER FLIES 
Robber flies are mostly large to very large (fig. 169). Some 
have long, tapering abdomens; others are stout-bodied and re- 
semble bumblebees. All are rather hairy. They are predacious on 
other insects and occasionally on their own kind. The larvae of 
Tolmerus notatus (Wield.), Leptogaster flavipes Loew, Laphria 
index McAtee, L. flavicollis Say, and L. thoracica (F.) have been 
collected from decaying wood infested with cerambycid and other 
coleopterous larvae. Larvae of certain other species feed on grass- 
hopper eggs and white grubs. 
COURTESY CONN. AGR. EXPT. STA. 
FiguRE 169.—Adult of a robber fly, 
Asilus sericeus. 
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