50 OHIO STATE ACADEMY OF SCIENCE. 
TABANUS COSTALIS Wiedemann. 
Length 12-14 mm. Palpi yellowish, antennae brownish with the 
annulate portion darker; thorax including the scutellum uniformly grayish 
yellow pollinose; legs largely black,-base of front tibiae and the middle 
and hind tibiae except at apex yellowish; wings hyaline with the costal 
cells yellowish, veins yellowish; abdomen above alternately striped with 
black and grayish yellow. 
Female: Frontal callosity black, above with a very much nebo 
prolongation the part of which adjacent to the callosity is sometimes 
obliterated leaving the upper part as a separate spot. 
Male: This sex is much like the female and easily associated with 
it, but there is a tendency toward obliteration of the distinct markings 
of the abdomen, the black of the female is replaced by brownish and 
the stripes may blend so that the whole base of the abdomen is prac— 
tically one color. 
Habitat: Common all over Ohio. 
This species may be confused with nigrovittatus, sagav and 
fulvulus, all of which have the yellowish costal cells. The last 
two are usually larger than costalis, and the spots on the sides 
of the abdomen above are not contiguous; the former has the 
apex of the third tibia reddish, while costalis has the same part 
black. So far nigrovittatus is known from the Atlantic coast only. 
The green- -headed fly, as costalis is called, is one of our worst 
stock pests. It is most abundant during August, when:a large 
number of other annoying flies are numerous. 
TABANUS EPISTATUS Osten Sacken. 
Length 14-16 mm. Eyes pilose, ocelligerous tubercle present; thorax 
black with rather prominent gray stripes; wing hyaline with extreme 
base, costal cells and veins brownish, abdomen broadly reddish on the 
sides. 
Female: Subcallus often although not always denuded; palpi dis- 
tinctly thickened and rather short, front gradually widened above, 
frontal callosity small, shining brown, rounded above, and separated 
from a linear shining spot above it by a pollinose interval. Legs brown, 
femora lighter than the other parts. 
Male: Subcallus not denuded in the specimens before me, head 
rather small, eyes distinctly pilose; palpi short and thick. 
Habitat: . Sandusky; taken in the tall grass on the border 
of a marsh July 6th. 
__ This species is very close to affinis, but easily separated from 
it by the enlarged palpi. The palpi in affinis até long and slender. 
The. color of the abdomen is variable, in some specimens 
there is a distinct black middorsal stripe, but in others this stripe 
is more or less broken up by the encroachmient of the reddish, 
