TABANIDA OF OHIO. 57 
-posterior margin and with darker hairs on the basal part, wings hyaline, 
legs somewhat variable but inclined to black with the basal part of the 
tibiae yellow, abdomen with a prominent middorsal row of gray triangles 
and gray spots on each side. 
Female: Palpi light yellow front noticeably gradually widened 
above, frontal callosity below nearly as wide as the front, about square, 
above with a narrowed extension which reaches half way to the vertex; 
segments of the abdomen above with gray posterior margins which 
expand into prominent triangles in the middle; first two segments nearly 
uniform gray on the sides, next three segments with extensive gray 
markings enclosing a black patch on the anterior part of the segments, 
last three segments largely black on the sides; the black on the second 
segment takes the form of two spots connected before and produced 
laterally so as to include the anterior margin of the segment; on the 
following three segments the black takes the form of four spots, the middle 
two of which are united before. 
Male: Antennae black, palpi darker than in the female, and the 
legs may be said to be uniform black except that the bases of all the tibiae 
are pale; abdomen with more gray than in the other sex but the arrange- 
‘ment is the same. 
Habitat: Oxford, Georgesville, Loudonville and Medina. 
The two sexes are easily associated. The species may be 
confused with mvosus, coffeatus, longus and some of the species 
with hairy eyes, but these latter need not enter into the case if 
care is exercised. From longus its uniform black instead of red- 
dish color is distinctive, coffeatus has only the posterior margins 
of the segments white on the sides, and a reference to the descrip- 
tion of mivosus above will reveal the difference between vivax and 
that species. 
The larve live in streams, and the females have been observed 
ovipositing on stones in ripples. The egg mass is not so convex 
as in many other species, but covers more surface. 
