With it occurs the unio littoralis, now living in the Seine and Loire.
"The Student's Elements of Geology"
Sir Charles Lyell
In the midst of these leaf-beds in Studland Bay, Purbeck shells of the genus unio attest the fresh-water origin of the white clay.
"The Student's Elements of Geology"
Sir Charles Lyell
Traced in one direction, or eastward towards Herne Bay, the Woolwich beds assume more and more of a marine character; while in an opposite, or south-western direction, they become, as near Chelsea and other places, more fresh-water, and contain unio, Paludina, and layers of lignite, so that the land drained by the ancient river seems clearly to have been to the south-west of the present site of the metropolis.
"The Student's Elements of Geology"
Sir Charles Lyell