24 THE SEX-COMPLEX 



The influence the factors concerned in the implantation of the fertilized 



of the cells of 



the corpus OVUm. 



luteum on with regard to the influence of the corpus luteum on 



cyclical ° . _ 



changes in the ovarian and uterine cycles — that is, on ovulation 



Seru V s aryand and on menstruation— it has been suggested by Beard 1 , 



Pr6nant 2 and others, and experimentally established 



by Loeb 3 , that the corpus luteum of one period during 



its maturity prevents ovulation, and that removal of the 



corpus luteum, or corpora lutea, accelerates subsequent 



ovulation. In other words, ovulation is incompatible 



with the function of the corpus luteum. 



Pearl and Surface 4 obtained confirmatory evidence 

 of this by another method of investigation. They found 

 that injections of an extract of corpus luteum prevent or 

 retard ovulation in the fowl. Loeb's 5 experiments of 

 the same character on guinea-pigs were, however, not 

 conclusive. 



Since the cyclical changes in the uterus are almost 

 certainly dependent normally on cyclical ovarian activity, 

 it follows that a cause that suppresses ovulation also, 

 prevents menstruation or * heat '. In other words, the 

 formation of a corpus luteum has a definite time relation- 

 ship to the uterine cycle. And it appears that this is 

 so in the lower animals, although accessory factors such 

 as copulation may be required to effect the rupture of 

 the ripe follicles; but in the human subject I, like 

 Lawson Tait 6 and others, have often observed the 

 absence of any ripe follicle or corpus luteum in relation 

 to menstruation. There is no doubt, therefore, that the 

 whole question of the connexion between the uterine 

 cycle and the ovarian cycle requires further investigation, 

 in spite of the excellent work of Loeb and others to 

 which reference has been made. 



1 Beard, J., Anat. Anzeiger, 1897, vol. xiv, p. 97. 



2 Prenant, A., Rev. Gen. des Sci, 1898, p. 646. 



3 Loeb, L., Deuts. Med. Woch., 1911, vol. xxxvii, p. 17 ; Biol. Bull, 

 1914, vol. xxvii, p. 30. 



4 Pearl, R., and F. M. Surface, Journ. Biol. GTiem., 1914, vol. xix, 

 p. 263. 



5 Loeb, L., Trans. Amer. Gynecol. Soc., 1917, vol. xlii, p. 172. 

 • Tait, L., Med. Times, Lond., 1884, vol. i, p. 619. 



