Geoscience Reference
In-Depth Information
Fig. 3.7
Map showing the Pliocene Crag areas of East Anglia (Harmer
1910b
)
compiled directly from Taylor's manuscript, the appendix was entirely the work of
Dale and contained his account of the geology of the Harwich Cliff which he
described as 'a sort of promontory, which divides Orwell Haven from the Æstu-
arium (Dovercourt Bay) contained between that and Walton Naze or Ness'. Over
40 fossils from the Harwich Cliff described by Dale have now been classified
under the Red Crag formation according to the current terminology.
Dale also discussed the problem about the origin of fossils which had puzzled
oryctologists for many years. For example, whilst the palaeontologist, Robert Plot
(1640-1696) held the view that they were lapides sui generic, produced by some
plastic power inherent in the crust of the earth, Robert Hooke (1635-1703) pre-
sciently believed that they owed their form and figuration to the shells of certain
shellfish and believed that such fossils provided reliable clues to the past history of
life on earth. Despite the objections of contemporary naturalists such as John Ray
(1627-1705) who found the concept of extinction theologically unacceptable;
Hooke stated that in certain cases they might represent species that had become
extinct through some geological disaster.
Dale's account of the Red Crag fossils in the Harwich Cliff is especially
valuable as it preserves a record of the contents of a former outlier of the Essex
coast which was later lost to the sea. His name is preserved by a species of fossil
shellfish, Buccinum dalei (Dale's whelk: Liomesus dalei). In naming it, James
Sowerby (1757-1822), himself a student of the crag fossils, said he did so 'to
