348 THE PHYSIOLOGY OF REPRODUCTION 



experiments undertaken by the author in collaboration with 

 Mr. Carmichael, 1 no systematic investigation ever appears to 

 have been attempted upon the effects of hysterectomy. 



In our experiments we removed the uterus, either entirely 

 or leaving only the cervix, from a number of very young 

 immature rabbits. The animals were killed after they had 

 become fully grown in some cases not until ten months after 

 the operation. In every experiment the ovaries were found to 

 have developed normally. In some cases also copulation was 

 observed on the rabbits being put with the buck. Many of the 

 ovaries contained typical corpora lutea, showing that ovulation 

 had taken place. Also in four experiments on fully grown rats 

 hysterectomy was performed, and the animals were killed several 

 months subsequently. The ovaries in no instance showed any 

 indications of atrophy. On the other hand, marked uterine 

 degeneration was observed in rats after the removal of the 

 ovaries for shorter periods of time. 2 



As a result of these experiments, it may be concluded that 

 the growth and development of the ovaries is in no way de- 

 pendent upon the presence of the uterus. Such a conclusion is 

 no doubt opposed by some of the clinical evidence, but it is 

 one which was to be expected on phylogenetic grounds, since the 

 uterus is an organ which came into existence comparatively 

 recently in the course of vertebrate evolution, whereas the 

 ovary is common to all Metazoa. It is possible, in those surgical 

 cases in which the ovaries underwent atrophy after the removal 

 of the uterus, that this was due to vascular interference. 3 



1 Carmichael and Marshall, Proc. Roy. Soc., loc. cit. 



- Marshall and Jolly, "Results of Removal and Transplantation of 

 Ovaries," Trans. Roy. Soc. Edin., vol. xlv., 1907. 



3 Boston has recorded four cases of women where the uterus was con- 

 genitally absent, but in whom the development of the breasts and other 

 changes relating to puberty excepting menstruation were experienced. 

 Sentiment, sexual desire, and sexual sensation are stated to have been normal 

 in each case ("Absence of the Uterus in Three Sisters and Two Cousins," 

 Lancet, Part I., Jan. 1907). It may also be mentioned that Sellheim found 

 that removal of the oviducts in pheasants does not result in a shrivelling 

 up of the ovaries and the assumption of secondary male characters as has 

 been stated (Zeit. f. Qyniik., 1904, No. 24). It has not been determined 

 whether the generative organs (apart from the uterus) undergo the character- 

 istic prooestrous changes after hysterectomy, since these changes are com- 

 paratively slight and difficult to detect in rabbits. 



