The Fuller's Earth of the Whatley area, southwestern England, represents an outlier resting on Inferior Oolite, of middle Jurassic age, which in turn lies on Carboniferous limestone. The Fuller's Earth was formerly thought to rest directly on the Paleozoic, thereby giving evidence for dating the final submergence of the Mendip hills as Bathonian. The evidence now indicates that submergence occurred before the end of the Bajocian. The Fuller's Earth fauna is listed, and a description of the ammonite fauna, by W. J. Arkell, is appended.