1. Department of Molecular and Cell Biology University of Connecticut, Storrs, CI 06268, and Marine Biological Laboratory, Woods Hole, MA 02543.
2. Department of Biological Sciences, Illinois State University, Normal, IL 61761.
3. Zoecon Research Institute, Palo Alto, CA 94304.
4. Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06268.