Presents four significant early fossils with thorough descriptions and detailed information suitable for in-depth study. Set includes 4 books: Ammonites, Brachiopods, Crinoids, and Trilobites. Written by Montessorians Doug and Claudia Mann and designed as an extension to the Time Line of Life, this set offers children many opportunities to solidify their understanding and expand their research. Invaluable additions to your library, all books are updated with current terminology and scientific developments. Paperback.