244 
The Ohio Naturalist. 
[Vol. V, No. 2, 
at the sides of the antennae are not so black or so thick as in }'our 
specimen, and the forehead is not so dark.” 
The specimen I sent Miss Ricardo measures fully Ki milli- 
meters in length. As Bigot gives the length of his tvpe as 11 
millimeters, we see how misleading his statements may be. 
Tabanus sonomensis Osten Sacken. The antennae are black 
or they may be dark red at base, the third segment is narrow 
with the basal portion longer than the annulate portion, and the 
basal prominence is small ; the palpi are brownish yellow clothed 
with black hairs, the sides of the front in the female are nearly 
parallel, the abdomen is ])lainly red on the sides. The usual dor- 
sal row of gray triangles may be seen in well preserved specimens 
but no lateral rows are apparent. The red on the sides of the 
abdomen is somewhat variable in extent, and the posterior mar- 
gins of the segments are furnished with a fringe of vellow hairs. 
The wings are hyaline but many of the veins, especially the 
cross-veins and furcation of the third vein, are margined with 
fuscous. 
The species is separated from rhombicus and its allies Viy the 
nearly complete absence of lateral gray spots on the abdominal 
segments ; and from affinis by the narrower third antennal seg- 
ment, as well as its smaller average size, from epistatus by the 
blacker antennse, and from phaenops by its larger average size 
and clouding of the cross- veins and furcation of the third vein. 
The several males I have are colored like the females and 
easily associated with them, although the fringes of hairs on the 
])osterior margins of the abdominal segments are not so conspic- 
uous in this sex. Length lo to 18 millimeters. 
I consider haemaphorus Marten a synonym of sonomensis. 
Tabanus susurrus Marten. The antennae are red with the 
annulate portion of the third segment black ; the wings are hya- 
line but there are faint clouds on the margins of the cross-veins 
and at the furcation of the third vein. All the femora, the apex 
of each anterior tibia, and the anterior tarsi are lilack or dark 
brown, other parts of legs red. except darker coloration on some 
of the tarsal segments. The abdomen is red on the sides of the 
first three or four segments. Specimens from Wyoming collected 
bv Morrison. IMarten’s type was from Montana. Length 13 
millimeters. 
Tabanus venustus Osten Sacken. This species is known from 
all others of its genus bv the large irregular dark patches on the 
wings. Eyes naked. Length 14 to Ki millimeters. Taken as 
far west as Oklahoma. 
Tabanus zonalis Kirby. This distinct species has the wings 
uniformly tinged with yellowish and the abdominal segments are 
black anteriorly and liroadly yellowish posteriorly. The anten- 
na are red but the apex of the third segment may be black, palpi 
