This volume gives descriptions and ranges of the 377 species of mosses known for Michigan. In addition, 147 figures, beautifully executed, provide illustrations that admirably assist in the difficult task of identifying mosses. Keys are provided to the genera and species, and a glossary, bibliography and index are other important sections of the book. An introductory portion presents the history of bryological exploration of Michigan and an account of the life history of mosses. A large number of references to treatments of mosses in other works is given. Since many species of mosses have a wide range, this book should be useful in many other states.