GrATENBY — Notes Oil the Human Ovary. 85 



have apparently shown that liquor folliculi extract itself contains the property 

 of indiicing those changes which were once supposed to be caused, partly at 

 least, by the corpus luteum. If, then, the follicle cells, during the growth of 

 the Graafian follicle, are able to produce such a hormone, it is difficult to 

 account for the subsequent extraordinary modification of the follicle cells into 

 peculiar luteal cells. It is also difficult to understand why Allen and Doisy 

 get negative results with corpus luteum extracted in the same way as liquor 

 folliculi. 



It is evident that my views, or rather the opinions I have formed on the 

 basis of the work of certain continental embryologists, as to the physiology of 

 this period of the oestrus cycle will need re-examination and probably 

 modification. Until further work has been carried out it would be injudicious 

 to comment at length on the physiological aspect of this problem. 



The main purpose of this paper has been to describe the minute cytology 

 of the lutein cells ; but there are one or two facts which arise in connexion 

 with the subject of menstruation and the raised nutrition of the uterus. 



Fraenkel believes that heat and menstruation are brought about by 

 secretions from the corpus luteum ; but, as Marsliall has pointed out, Fraenkel's 

 theory is disproved by the fact that ovulation in most mammalia does not 

 occur until oestrus, or at any rate, until the end of the prooestrum, and 

 consequently active corpora lutea are not present in the ovaries. Marshall 

 says : " Seeing that the corpus luteum is not responsible for inducing 

 menstruation, it becomes necessary to conclude that either the follicular 

 epithelial cells or the interstitial cells of the ovarian stroma (or both of these) 

 are concerned in bringing about the process (of menstruation)." 



Marshall's brilliant prophecy seems to have been proven by the American 

 observers, Allen and Doisy, whose work has apparently dismissed Fraenkel's 

 hypothesis of menstruation. 



The lutein gi-anules, so called, in the human corpus luteum, are arranged 

 like the mitochondria, and the fact that all the granules are equal in size, 

 points to the conclusion that the lutein granules are formed from the 

 mitochondria. The mitochondria presumably swell in size and become loaded 

 with the lipochrome which gives the corpus luteum its characteristic 

 appearance. I know of no case where neutral fat appears within any cell in 

 the form of chains of minute granules all the same size. Corner states shortly 

 that he found mitochondria in the corpus luteum of the sow, and mitochondria 

 have been described in the luteal cells of various mammals. The mi tochondria 

 and Golgi elements in many invertebrate ova contain a lipochrome which 

 colours the egg bright yellow or brownish, and there seems good reason for 

 believing that in the case of the human corpus we have something of the same 



