Assemblages of shells of the burrowing brachiopod Lingula squamiformis in Carboniferous shale overlying terrestrial fire clay and underlying marine limestone in Fife, Scotland, are defined as a biocoenosis. In terms of ecologic relationships, causes of death, and possibilities of posthumous shell transport of living lingulids, the paleoecologic relationships of the Carboniferous species are interpreted. The data indicate that conditions during the successive stages of transgression fluctuated around the limits of environment tolerance of the species.