Acknowledgments
Reading edition
The authors thank Bryan A. Jowers, Glendale, California, for the excellent winter silhouettes. For help in obtaining specimens or photographs of species not easily accessible to us, we thank the following: Roger W. Barbour, University of Kentucky; William Harlow, College of Environmental Science and Forestry, State University of New York; Richard Johnson, Caroline Dormon Nature Preserve; Betty E. Lemon, University of Southwestern Louisiana; R. Dale Thomas, Northeast Louisiana University; and Lino Della-Bianca and Edwin R. Lawson of the U.S. Forest Service.