Note on some Ichthyosaurian Remains from Kimmeridge Bay, Dorset

Abstract

These remains consist of several teeth and of fragments of a skull transmitted to me for examination last summer by J. Mansel Pleydell, Esq., F.G.S., to whom I have been already indebted on several occasions for opportunities of bringing under the Society's notice Saurian fossils from the Dorsetshire Kimmeridge beds. Unfortunately, as so commonly happens when the extrication of fossils from the shale is attempted by unskilled labourers, the bones were smashed into so many pieces as to render the restoration of the skull quite impossible. Estimated by the size of the broken pieces, the snout was probably not less than three feet long, and it was proportionately stout. Of the teeth some are shorter, more curved, and relatively stouter than the others. In both forms the crown is bluntly pointed, its base passes evenly into the root without any separating cingulum, and the proximal end of the root is laterally compressed, which gives its cross section an oblong figure (fig. 8), the longer sides of which are parallel with those of the dentary groove. The crown is strongly striated; the striæ diminish regularly from the base to the apex, near which they break up into lines of minute tubercles, which are continued to the very extremity. The most perfect of the longer teeth (only the extreme tip of the crown of which is missing) is 30 1/6 lines (English long, of which the crown forms 8 1/6 lines (figs. 1-3). The base of