Notes on the proportion of the sexes in dogs / by Walter Heape.

  • Heape, Walter, 1855-1929.
Date:
[1907]
Catalogue details

Licence: In copyright

Credit: Notes on the proportion of the sexes in dogs / by Walter Heape. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    1/32
    [Extracted from the Proceedings of the Cambridge Philosophical Society, Yol. xiv. Pt. n.] Notes on the Proportion of the Sexes in Dogs. By Waltek Heape, M.A., F.B.S., Trinity College, Cambridge. [Received 20 February, 1907.] Introduction. In the following paper I have confined myself to the facts presented by the records I have collected. I do not propose here to enter into a detailed argument regarding the causes which influence the proportion of the sexes produced by various animals, but would preface my remarks with a very brief general statement of certain aspects of that problem, as they appear to me. For generations it has been believed that the sex of an embryo is determined by extraneous forces exerted during the development of the embryo. The subject has always excited great interest among breeders and there is a huge literature dealing with it. I have myself noted titles of over 600 papers and books in which a great variety of causes have been urged as influencing the sex of the offspring and numerous theories published on methods to be adopted in order to regulate the proportion of the sexes which are born. A very large section of this mass of literature has been written on the assumption that sex is determined during em- bryonic life, that it can be and is normally determined in accordance with conditions which affect the growing embryo. But it seems clear, as I will show below, that both the ovum and the spermatozoan are themselves sexual, that the latest