As Norman states, Murchison's geological research in the Welsh borderland and South Wales brought to an end the confusion hitherto surrounding the so-called "Transition" rocks. "Murchison was the first to establish a uniform sequence of Transition strata, to which he gave the name 'Silurian' after a British tribe; these strata constituted a major system with uniform fossil remains, displaying an abundance of invertebrates and a complete lack of the remains of vertebrates or land plants." The implications for the evolutionary history of the earth were enormous. Illustrated on previous page.