400 GYNECOLOGY 



plantation of the fertilized ovum, Fraenkel removed the ovaries 

 from thirteen rabbits, one to six days after copulation. Later these 

 animals were killed, and in no instance was an ovum found in the 

 uterus. In another series only one ovary was removed, and this 

 did not interfere with gestation. It seemed, therefore, that im- 

 plantation had been prevented by removal of both ovaries. 



In another series of rabbits the ovaries were removed after im- 

 plantation of the ovums, and it was found that their development 

 ceased, though they were not expelled from the uterus. 



Similar results were obtained when, instead of removing the 

 entire ovarian tissue, the corpora lutea were destroyed with a 

 cautery. It was found that development of the ovum might 

 continue if only one corpus luteum was left in the ovary. When 

 the ovaries were transplanted, destruction of the ovum occurred, 

 though after some delay. After burning the corpora lutea from 

 the ovaries, it was found that the uterus was much atrophied in 

 two weeks. 



This physiologic interpretation of the function of the corpus 

 luteum is worthy of the highest consideration. Hitherto, anatomic 

 explanations have been chiefly prevalent. Thus, it has been con- 

 sidered as forming an extra protective covering to the ripening 

 ovum, as a plug to check hemorrhage after bursting of the follicle, 

 and as a kind of splint steadying the tissues during the process of 

 healing. Clark has pointed out that it is evidently associated with 

 a method of repair, which leads to little formation of connective 

 tissue, and has well stated that if the ruptured follicles were healed 

 by the ordinary method, the ovary would be converted into a mass 

 of connective tissue, which would render the escape of ovums in- 

 creasingly difficult. 



On the other hand, Fraenkel and others who adopt the physio- 

 logic interpretation, emphasize the well-known structural resem- 

 blance of the fully-formed corpus luteum to a ductless gland, since 

 it consists of rows of large epithelioid cells - - the lutein cells, ar- 

 ranged somewhat radially, strands of delicate connective tissue 

 containing blood-vessels ramifying between the columns. Fraenkel 

 holds with Sobotta and others that the yellow body is derived from 

 the membrana granulosa, and that thus an epithelial origin is ob- 

 tained for the cells of the glandular organ. I have already pointed 

 out that many authorities hold that the corpus luteum is derived 

 not from the membrana granulosa, but from the connective tissue 

 external to the latter, while a considerable number hold that the 

 membrana granulosa is itself of connective-tissue origin. If the 

 latter view be correct, and the glandular nature of the corpus lu- 

 teum be established, such a marvelous transformation of connect- 

 ive tissue is without parallel in any other portion of the human 



