CHANGES IN THE OVARY 143 



to form a central plug in which there are no luteal cells. This 

 connective tissue contains numerous blood-vessels, so that the 

 fully developed corpus luteum is a highly vascular structure. 



Three hypotheses have been put forward regarding the 

 manner of formation of the corpus luteum. That of Paterson, 1 

 who supposed it to be derived from the blood coagulum left in 

 the cavity of the Graafian follicle after its discharge, gained few 

 or no adherents. The other two theories, those of von Baer '- 

 and Bischoff, 3 on the other hand, have each received consider- 

 able support. 



Von Baer regarded the corpus luteum as an entirely con- 

 nective tissue structure, in the origin of which the follicular 

 epithelium had no share ; while Bischoff concluded that the 

 luteal cells were formed by the hypertrophy of the epithelial 

 cells of the undischarged Graafian follicle. Among the principal 

 supporters of Von Baer's view appear the names of Leuckart, 

 His, Kolliker, Slavjansky, Gegenbaur, Benckiser, Schottlander, 

 and Minot. Those who have adopted the alternative theory of 

 Bischoff include Pfliiger, Waldeyer, Gill and Exner, Beigel and 

 Schulin. 4 



. To Sobotta 5 belongs the credit of being the first to deal 

 systematically with the question, and, with the publication of 

 his papers on the corpus luteum in the mouse, the controversy 

 entered upon a new phase. In Sobotta's investigation the 

 material employed was collected upon a definite plan, the 

 animals being killed at known intervals after coition, in re- 

 ference to the occurrence of which the period of ovulation had 

 been previously determined. In this way there was obtained 

 a large series of corpora lutea representing successive stages of 

 development. The investigation resulted in confirming BischofFs 



1 Paterson, " Observations on Corpora Lutea," Edinburgh Med. and Surg. 

 Jour., 1840. 



3 Von Baer, De Ovi Mammal iutn et Hominis Genesi Epistola, Lipsise, 

 1827. 



3 Bischoff, Entwickelungsgeschichte des Kanincheneies, Braunschweig, 1842. 



4 For an account of the older literature of the subject see Sobotta, " liber 

 die Entstehnng des Corpus Luteum der Saugethiere," Merkel and Bonnet's 

 Erychnisse dcr Anat. u. Entvick., vol. viii., 1899. 



5 Sobotta, " Uber die Bildung des Corpus Luteum bei der Maus," Anat. 

 Anz., vol. x., 1895 ; and Arch. f. Mikr. Anat., vol. xlvii., 1896. 



