DIPTERA. 531 
club-shaped, shining, pitchy ridge on the fore-crown: eyes bronze, parted 
above by a rather broad interval ; facets very small, but slightly increasing 
in size towards the inner fore part: sucker black, stout; lancets bright 
pale ferruginous ; palpi dark tawny, thickly clothed with very short black 
hairs: feelers black, long ; first and second joints clothed with black hairs ; 
third joint convex beneath, its horn very long, much curved downward ; com- 
pound joint long, hardly curved upward: chest grayish-black, dark ferru- 
ginous and tinged with hoary on each side, adorned with two slender hoary 
stripes: breast hoary, partly clothed with whitish hairs: abdomen slightly 
obconical, finely punctured, clothed with short black hairs, longer than the 
chest ; a patch of white hairs on each side of the first and second seg- 
ments, and another patch on the hind border of the fourth segment ; under 
side adorned with a patch of white hairs on each side of the hind border 
of every segment: legs black, clothed with short black hairs; foot-cushions 
tawny: wings gray, tawny at the base and along the fore border as far as 
the brand, which is dark brown; a large brown spot below the brand 
clouds also the borders of the veins in the disk ; wing-ribs ferruginous ; 
veins black, ferruginous towards the base and along the fore border ; 
angle of the tip cross-vein distinct, slightly obtuse, sending forth a short 
stump ; (in one wing of the insect described the angle is slightly rounded 
and has no stump) scales gray, with ferruginous borders ; poisers pitchy, 
with tawny tips. Length of the body 74 lines ; of the wings 16 lines. 
Columbia. 
TABANUS DETERSUs, Fem. 
Niger, thovacis lateribus pectore ventris vittis duabus et segmentorum mar- 
ginibus posticis ferruginets, antennis ferrugineis apice nigris, pedibus 
ferrugineis, tarsis antics piceis, alis cinereis. 
Body black: head tawny in front, clothed beneath with hoary hairs: 
_eyes bronzed; the facets as usual: sucker black; lancets and palpi ferru- 
ginous. feelers dark ferruginous ; first and second joints clothed with short 
black hairs; third slightly convex beneath, forming above a shallow and ex- 
tremely obtuse angle, whose fore side extends to the tip and is twice the 
length of the hind side ; compound joint black, slightly curved upward, much 
shorter than the third joint : breast and sides of the chest ferruginous, with 
a hoary tinge: abdomen linear, conical at the tip, much longer than the 
chest; hind borders of the segments and a broad stripe on each side be- 
neath dark ferruginous: legs ferruginous ; fore-feet and tips of the other 
