1. Asst. Prof., Dept. of Natural Resour. and Envir. Sci., Univ. of Illinois, W-503 Turner Hall, 1102 S. Goodwin Ave., Urbana, IL 61801. E-mail: gmcisaac@uiuc.edu
2. Deceased June 3, 1997; formerly, Prof., Dept. of Mgmt., Western Illinois Univ., Macomb, IL 61455.