Wednesday, February IG. Professor SEDGWICK, President, in the chair. The following gentlemen—Dr. James C. Somerville, Jun., John IFI'Donnell, Esq., John Evans, Esq., and John Badclams, Esq—were elected Fellows of the Society. A letter was first read from Peter Cun. ningham, Esq. dated Newcastle-on-Hunter's-River, New South Wales, October 10, 1829, and communicated by John Barrow, Esq., F.R.S. This letter was written with a view to give some insight into the former state of the interior of New South Wales, and was accompanied by a series of illustrative specimens. A Memoir was then read " On the Geology of the Island of Juan Fernandez, in the Pacific Ocean, by Alexander Caldcleugh, Esq., F.G.S."