Illinois Natural History Survey, Lorin I. Nevling, Chief
A Division of the Illinois Department of Energy and Natural Resources
Illinois Natural History Survey
Printed by authority of the state of Illinois
Editors: John Ballenot, Alison Fong Weingartner
On-line Editors: Sarah Jean Aston, Christine Mayer, Charlie Warwick
About the authors: Kevin S. Cummings and Christine A. Mayer are Associate Research Biologists with the Illinois Natural History Survey, Center for Biodiversity, in Champaign.
Partial funding for the preparation of this field guide was provided by the U.S. Fish & Wildlife Service, Region 3 Office, Twin Cities, Minnesota; the Illinois Department of Conservation, Division of Natural Heritage, Springfield, Illinois; and the Mussel Mitigation Trust, Cincinnati, Ohio. The Indiana Academy of Science provided partial funding for the second printing of this manual.
Library of Congress Catalog Card Number: 92-83870
To the memory of Dr. Max R. Matteson (1909-1990) and field biologists everywhere