Three of the species of Ablautus Loew described here have been on hand for several years and, as no additional material has become available, there seems to be no reason for delaying their description longer. These small robber flies inhabit the more arid regions of the West and Southwest and seem to prefer sandy localities in the sage brush. Osten Sacken commented on the fact that Ablautus mimus O. S. was associated with Lestomyia sabulonum O. S. on sandy soil and seems to mimic it; and Melander says, regarding Cyrtopogon ablautoides Mel., “The species presents a curious superficial resemblance to Ablautus mimus O. S., with which it is associated in the sandy desert region.”