The sub-family Anthracina differs from any other of the Bombylidæ, as well as from any other group of Diptera known to me, in that the second vein issues from the third at a point opposite or nearly opposite the small cross-vein, the distance being never greater than the length of that cross-vein; the course of the third vein at the place where the second vein issues from it, is perfectly straight, while in the other Diptera the third vein bends obliquely downward at the same angle that the second vein extends upward at its base.