THE EARLY JURASSIC SEQUENCE OF LYME REGIS, DORSET, ENGLAND AND ITS SIGNIFICANCE TO THE HISTORY OF GEOLOGY AND PALEONTOLOGY

The cliffs and foreshore of the small town of Lyme Regis on the south coast of England expose a 146 metre thick sequence of Early Jurassic (Hettangian–Pliensbachian) marine limestones and mudstones: the Blue Lias Formation and the overlying Charmouth Mudstone Formation, the lowest units of the Lias Group. For several centuries these formations have been a rich source of ammonites, belemnites and other invertebrates, as well of ichthyosaurs and plesiosaurs, to tourists, collectors and museums.

The marine reptiles first came to scientific attention in the early decades of the nineteenth century, largely due to the discoveries of a family of fossil dealers whose most famous member was Mary Anning (1799–1847). Anning and her family recovered the first scientifically described ichthyosaurs, the first complete plesiosaur, and the first British pterosaur to be identified. Anning was also the first to recognise the true nature of bezoar stones as fossil feces; that the crinoid Pentacrinites lived attached to floating driftwood; and that some cephalopod fossils preserved their ink sacs which could be reconstituted as drawing sepia.

Within Mary Anning’s wide network of friends and clients were three of the leading geologists of the time who had close personal associations to the town and who did much to report and publicise her discoveries and contribute to both her fame and that of the locality: William Buckland (1784–1856), William Conybeare (1787–1857) and Henry De la Beche (1796–1855). Anning’s finds from Lyme Regis formed the basis of De la Beche and Buckland’s c.1830 paleoenvironmental reconstruction, Duria Antiquior, lithographs of which were sold to benefit her.

This famous coastal section, with its important historical associations with a key period in the development of geology and the source of so many significant discoveries in the early nineteenth century, now lies within the Jurassic Coast UNESCO World Heritage Site.