In 1818 appeared Amos Eaton’s Index to the Geology of the Northern States, having 54 pages, and in 1820 came the second edition, “wholly written over anew,” with 286 pages. The theory of the later edition is still that of Werner, with “improvements of Cuvier and Bakewell,” and yet one sees now-a-days but little in it of the far better English text-book. Eaton did very little to advance philosophic geology in America. What is of most value here are his personal observations in regard to the local geology of western Massachusetts, Connecticut, southwestern Vermont, and eastern New York (=1=, 69, 1819; also Merrill, p. 234). We come now to the most comprehensive and advanced of the early text-books used in America. This is the third English edition of Robert Bakewell’s Introduction to Geology (400 pages, 1829), and the first American edition “with an Appendix Containing an Outline of his Course of Lectures on Geology at Yale College, by Benjamin Silliman” (128 pages). Bakewell’s good book is in keeping with the time, and while not so advanced as Conybeare and Phillips’s Outlines of 1822, yet is far more so than Silliman’s appendix. The latter is general and not specific as to details; it is still decidedly Wernerian, though in a modified form. Silliman says he is “neither Wernerian nor Huttonian,” and yet his summary on pages 120 to 126 shows clearly that he was not only a Wernerian but a pietist as well. _Unearthing of the Cenozoic and Mesozoic in North America._ _The Discerning of the Tertiary._—The New England States, with their essentially igneous and metamorphic formations, could not furnish the proper geologic environment for the development of stratigraphers and paleontologists. So in America we see the rise of such geologists first in Philadelphia, where they had easy access to the horizontal and highly fossiliferous strata of the coastal plain. The first one to attract attention was Thomas Say, after him came John Finch, followed by Lardner Vanuxem, Isaac Lea, Samuel G. Morton, and T. A. Conrad. These men not only worked out the succession of the Cenozoic and the upper part of the Mesozoic, but blazed the way among the Paleozoic strata as well. Thomas Say (1787–1834), in 1819, was the first American to point out the chronogenetic value of fossils in his article, Observations on some Species of Zoophytes, Shells, etc., principally Fossil (=1=, 381). He correctly states that the progress of geology “must be in part founded on a knowledge of the different genera and species of reliquiæ, which the various accessible strata of the earth present.” Say fully realizes the difficulties in the study of fossils, because of their fragmental character and changed nature, and that their correct interpretation requires a knowledge of similar living organisms.