Leiorhynchus kelloggi Hall has been found only in the uppermost beds of the Middle Devonian Silica Shale, Plum Brook Shale, and Arkona Shale. The species is found in argillaceous biomicrites and argillaceous fossiliferous micrites deposited in deeper sublittoral environments. Specimens from the Arkona Shale and Plum Brook Shale, on the east side of the Findlay Arch, show a closer morphologic similarity to each other than to specimens from the Silica Shale, on the west side of the Arch. Shell structure, ontogeny, faunal and lithologic associations, and correlation are examined.