BY H. LEIGHTON KESTEVEN. 137 



that portion of the following paper which deals with the litera- 

 ture. This paper was written in 1908, and since then I have 

 had no opportunity of keeping abreast of the cognate current 

 literature, and, at present, T am beyond the reacli of a libraiy, 

 I believe, however, that even though this contribution is thus 

 nine years old at date of printing, it is deserving of publication. 



The ovarian epithelium in the young female is composed of 

 fairly regular, cubical oogonia.* The continued division of these 

 gives rise to the mass of ultimate oogonia which fills not only 

 the lumen of the ovary, but also the anterior portion of that of 

 the oviduct. It is while lying free in the lumen, in this mass, 

 that the ultimate oogonium advances so far towards maturity, 

 that it may thereafter be regarded as the primary oocyte. 



AVhen first shed into the lumen of the gland, the ultimate 

 oogonium is a small, rounded, hyaline cell. Its comparatively 

 lai'ge nucleus may contain only one karyosome, or it may contain 

 two, three, or four of approximately equal size. The size of the 

 inicleus is defined by the nuclear membrane alone; that is to say, 

 the nucleoplasm is hyaline, and takes no stain, nor is it difl^'eren- 

 tiated from the cytoplasm by the presence of a discernible chro- 

 matin-reticulum (Fig. 1). In those cases where there is only one 

 karyosome, I am unable to find that this a»e differs from the three 

 or foul' in other cases, nor among these is there any difference 

 inter se. 



The cell now enlarges. The nucleus, increasing in size at a 

 greater rate than the cell, comes ultimately to fill nearly the 

 whole cell. 



When this process has reached the stage depicted in Fig. 2, a 

 chromatin-reticulum is well established, and the karyosomes have 

 increased in number. In short, the period is characterised by an 

 increase of chromatin. 



As soon as this increase has reached its maximum, the reticulum 

 becomes broken down, till, as depicted in Fig. 3, in place of a 

 network, there is present a great number of fine granules of 



* The description is of material stained with htematoxylin without any 

 counter stain. 



