Excerpt from Bulletins of American Paleontology, Vol. 20: 1933 1934 To this period also belongs the work of Dr. Antonio Raimondi covering a space of nearly 50 years of systematic research on the geography and topography of Peru. Raimondi made impor tant observations on geology, incorporating most of this infor mation on his maps and he apparently used the fossils he collect ed as a guide in determining the age and distribution of the sedi mentary formations. He sent his fossils to Wm. Gabb5 for de scription, accompanying them with a letter in which he gave a concise and interesting outline of the geographic distribution of the sedimentary formations in Peru. According to his idea, Cretaceous together with Jurassic and Triassic rocks are princi pally distributed in the Western Cordillera while the Eastern Cordillera is of greater age and composed mainly of schists and older rocks. The collection obtained 'by Raimondi was described and figured in 1877 by Wm. Gab-136. Gabb seldom ventured an opinion on the age of the scattered collections and in most cases he simply stated the age of the beds according to the opinion of Raimondi. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.