1. Haskins, R. H., Tulloch, A. P., and Micetich, R. G., Canad. J. Microbiol., 10, 187 (1964).
2. Hendrix, J. W., Science, 144, 1028 (1964).
3. Klemmer, H. W., and Lenney, J. F., Phytopathology, 55, 320 (1965).
4. Tukey, J. W., in Experimental Design, edit. by Federer, W. T. (The Macmillan Co., New York, 1955).
5. Fothergill, P. G., and Hide, D., J. Gen. Microbiol., 29, 325 (1962).