Review of: Richardson’s Guide to the Fossil Fauna of Mazon Creek, edited by Charles W. Shabica & Andrew A. Hay. Northeastern Illinois University, Chicago, Illinois, 1997: XVIII + 308 pp., 385 figs., 4 tables, 1 faunal list; $75.00 (hard cover) ISBN 0-925065-21-8. Since the last century, the area around Mazon Creek in northern Illinois, about 100 km southwest of Chicago, has been known for its Pennsylvanian fossils. Mainly plant fossils were found along Mazon Creek and in the open coal pits of that area until the 1950s. Langford (1958, 1963) was the first to give a compilation of the flora and fauna of Mazon Creek. He listed and figured 60 genera including 71 species of animal fossils. As the coal mining moved farther south, and Pit 11 was opened in the 1950s, the relationship between plant and animal fossils in the iron concretions drastically changed. In this new book, the number of animal genera recorded has increased three times over that of Langford (1963), omitting about another 130 insect genera.