[16.]

Goodale, H.D. A Feminized Cockerel. Jour. Exp. Zool. Vol. 20, pp. 421-8.

[17.]

Ward, Lester F. Pure Sociology. N.Y., 1903, pp. 322f.

[18.]

Ellis, Havelock. Man and Woman, 4th Ed. London, 1904. Ch. XVI.

[19.]