1. RISEBROUGH, R. W., REICHE, P., PEAKALL, D. B., HERMAN, S. G., and KIRVEN, M. N., Nature 220, 1098 (1968).
2. PEAKALL, D. B., and LINCER, J. L., Bio Science 20, 958 (1970).
3. RISEBROUGH, R. W., in Report of the Secretary's Commission on Pesticides and their Relationship to Environmental Health, 258, (1969), U. S. Dept. of Health Education and Welfare.
4. DYMENT, P. G., HEBERTSON, L. M., DECKER, W. J., GOMES, E. D., and WISEMAN, J. S., to be published.
5. DALE, W. E., CURLEY, A., and CUETO, C., Life Science 5, 47 (1966).