This book will be of particular interest to those interested in applied fields of biology, such as conservation, forestry, and wild life. The southern twelve counties of Illinois, a total of 4,355 square miles, comprise the area covered in this book. It is an area in which both northern and southern flora specimens abound. A wide variety of plant species grow in this area, and nearly 200 new plants not formerly identified with this area have been included in the listings.