482 CATHARINE LINES CHAPIN 



tion of a smaller amount, allowing some development toward the 

 female condition. This is also suggested by the partial union 

 of the horns of the uterus in the 16.3 cm. free-martin T6. 



b. The arrangement of cells in the sex cords of the free-martin 

 as they are arranged in the seminiferous tubules of the male and 

 the relatively large size of the sex cord region suggest an early 

 introduction of the male influence, made before the beginning or 

 early in the process of degeneration of medullary cords which 

 normally take place in the female, or the introduction of a 

 sufficiently large amount of male secretion to inhibit female 

 development completely and to cause development toward the 

 male condition. The development of the Miillerian ducts of 

 the 22.5 cm. free-martin, T4, into contorted seminal vesicles of 

 small diameter suggests that the male hormone was introduced 

 into the female earlier or in larger amount in this case, than in 

 the 28 cm. free-martin, T12, in which the Miillerian ducts are 

 still straight ducts of large diameter. 



BIBLIOGRAPHY 



Allen, B. M. 1904 Embryonic development of testis and ovary of mammals. 



Am. Jour. Anat., vol. 3, p. 89-141. 

 Hart, D. Berry 1909 Reproductive organs of the free-martin. Proc. Roy. 



Soc. of Edinb., vol. 30, 1909-10. 

 LiLLiE, F. R. 1916 The theory of the free-martin. Science, N. S., vol. 43, pp. 



611-613. 



1917 The free-martin; a study of the action of sex-hormones in the 



foetal life of cattle. Jour. Exp. ZooL, vol. 23, pp. 371-452. 

 MacCallum, J. B. 1902 Wolffian body in higher mammals. Am. Jour. Anat., 



vol. 1, pp. 245-260. 

 Paton, D. N. 1913 Regulators of Metabolism. MacMillan & Co. 

 ScHOENFELD, H. 1901 La Spermatogenese chez le taureau. Arch, de Biol. 



T., 18, pp. 1-64. 

 Whitehead, R. H. 1904 Development of the interstitial cells of Leydig. 



Am. Jour. Anat., vol. 3, pp. 167-182. 

 The literature on the free-martin, and on the interstitial gland and the effect 

 of its secretion is included in the bibliography of the preceding paper by Prof. 

 F. R. Lillie. 



