10 Pages in Charles Darwin's Library associated with "strata/epochs - silurian"

Contributions to the natural history of the United States of North America.
By: Agassiz, Louis,
Publication info: [s.n.] :[s.n.],n.d..
Pages: Page 31 Page 100
A manual of elementary geology.
By: Lyell, Charles.
Publication info: [s.n.] :[s.n.],1855.
Pages: Page 424 Page 447 Page 448 Page 449 Page 450 Page 451 Page 458 Page 463