_The Age of Mammals_; by Henry Fairfield Osborn. A classic in this field of literature, but for advanced reading. The book is now out of print. _The Dinosaur Book_; by Edwin H. Colbert. Published by the American Museum of Natural History, New York. An illustrated story of amphibian and reptilian evolution. _Down to Earth_; by Carey Croneis and William C. Krumbein. Published by the University of Chicago Press. An excellent popularization of the earth sciences—geology and paleontology. _Lexicon of Geologic Names of the United States_; compiled by M. Grace Wilmarth. Bulletin 896 (in two parts) of the United States Geological Survey. A rich source of information concerning the age, character, and distribution of geologic formations, with numerous references to fossil-bearing beds. _Bibliography of North American Geology_ (including paleontology); various bulletins of the United States Geological Survey. Where library facilities provide access to the technical literature of museums, universities, and scientific societies, this is a valuable aid in locating publications dealing with original work in paleontology. Bulletins 746 and 747 cover the years between 1785 and 1918; Bul. 823 (1918-1928); Bul. 937 (1929-1939); Bul. 938 (1940-1941); Bul. 949 (1942-1943); Bul. 952 (1944-1945); Bul. 958 (1940-1947); Bul. 968 (1948); Bul 977 (1949). Preparation is a continuous process with recent bulletins appearing at one or two year intervals. _Ancient Man in North America and Prehistoric Indians of the Southwest_; by H. M. Wormington. Published by Denver Museum of Natural History, City Park, Denver 6, Colorado. Both volumes contain authentic and up-to-date accounts of early American cultures. MAPS _Geologic Maps._ United States Geological Survey: map of the United States (1932); map of Colorado (1935). Geologic maps of a few other states are available; information regarding these may be obtained from state universities or state geological surveys. Note: Bulletins of the U.S.G.S. are purchasable from the Superintendent of Documents, Washington, D. C. Maps are sold by the Director of the Geological Survey, Washington, D. C. Transcriber’s Notes —Silently corrected a few typos —Restored one accidental omission in the Table of Illustrations —Retained publication information from the printed edition: this eBook is public-domain in the country of publication. —In the text versions only, text in italics is delimited by _underscores_. End of the Project Gutenberg EBook of Fossils: A Story of the Rocks and Their Record of Prehistoric Life, by Harvey C. Markman