The second error of the older geologists, according to Vanuxem, was the extension of the secondary rocks over “the western country, and the back and upper parts of New York.” They are now called Paleozoic. Some had even tried to show the presence of Jurassic here because of the existence of oölite strata. “It was taken for granted, that all horizontal rocks are secondary, and as the rocks of these parts of the United States are horizontal in their position, so they were supposed to be secondary.” He then shows on the basis of similar Ordovician fossils that the rocks of Trenton Falls, New York, recur at Frankfort in Kentucky, and at Nashville in Tennessee. “It is also certain that an uplifting or downfalling force, or both, have existed, but it is not certain that either or both these forces have acted in a uniform manner.... Innumerable are the facts, which have fallen under my observation, which show the fallacy of adopting inclination for the character of a class,” such as the Transition class of strata. He then goes on to say that in the interior of our country the so-called secondary rocks are horizontal and in the mountains to the east the same strata are highly inclined. “The analogy, or identity of rocks, I determine by their fossils in the first instance, and their position and mineralogical characters in the second or last instance.” It appears that Isaac Lea (1792–1886) in his Contributions to Geology, 1833, was the first to transplant to America Lyell’s terms, Pliocene, Miocene, and Eocene, proposed the previous year. The celebrated Claiborne locality was made known to Lea in 1829, and in the work here cited he describes from it 250 species, of which 200 are new. The horizon is correlated with the London Clay and with the Calcaire Grossier of France, both of Eocene time (=25=, 413, 1834). Timothy A. Conrad began to write about the American Tertiary in 1830, and his more important publications were issued at Philadelphia. His papers in the Journal begin with 1833 and the last one on the Tertiary is in 1846. The Tertiary faunas and stratigraphy have been modernized by William H. Dall in his monumental work of 1650 pages and 60 plates entitled “Contributions to the Tertiary Fauna of Florida” (1885–1903). Here more than 3160 forms of the Atlantic and Gulf deposits are described, but in order to understand their relations to the fossil faunas elsewhere and to the living world, the author studied over 10,000 species. Since then, many other workers have interested themselves in the Tertiary problems. Much good work is also being done in the Pacific States where the sequence is being rapidly developed.