1. Brambell, F. W. R., in Marshall's Physiology of Reproduction, edit. by Parkes, A. S. (Longmans, Green, London).
2. Zuckerman, S., in Sex Differentiation and Development, edit. by Austin, C. R. (Camb. Univ. Press, 1960).
3. Sirlin, J. L., and Edwards, R. G., Exp. Cell Res., 18, 190 (1959). Rudkin, G. T., and Greich, H. A., J. Cell Biol., 12, 169 (1962).
4. Brambell, F. W. R., Proc. Roy. Soc., B, 101, 391 (1927). Slizynski, B. M., Nature, 179, 638 (1957). Ohno, S., Makino, S., Kaplan, W. D., and Kinosita, R., Exp. Cell Res., 24, 106 (1961).
5. Odor, D. L., Amer. J. Anat., 97, 461 (1955).