Full reference: G. G. Simpson. 1935. Proceedings of the United States National Museum 83
Type specimen: U.S.N.M. no. 9314, a mandible (left lower jaw with C, P2-M3, and roots or alveoli of all other teeth). Its type locality is Gidley Quarry, which is in a Torrejonian terrestrial horizon in the Fort Union Formation of Montana.
Ecology: ground dwelling insectivore
Average measurements (in mm): M1 3.28 x 4.88, M2 3.42 x 4.92, M3 3.20 x 3.83, m1 3.26 x 2.56, m2 3.33 x 2.65, m3 3.98 x 2.42