816 DEVELOPMENT OF THE EEPEODUCTIYE ORGANS. 



The Ovary. — Considered as a glandular organ the ovary differs from 

 other glands by the absence from it of excretory ducts, and by the 



Fig. 610. Fig. 610. — Internal Okgans of a Female 



HUJIAN FcETtJS OF 3.| INCHES LONG. MAGNIFIED 



(from Waldeyer). 



o, the ovai7 full of primordial ova ; e, tubes 

 of the upper part of tlie WoMan body forming 

 the epoophoron (parovarium of Kobelt) ; \V, the 

 lower part of tlie Wolffian body forming the 

 paroophoron of His and Waldeyer ; W', the Wolffian 

 /'- .C"f ' 1 duct; M, the Miillerian duct; m, its upper 



/;",':; -V '' Y' fimbriated opening. 



/ .: separation of its conducting passages 



/: . from the glandular or productive part 



Ijj: -M of its structure. Like the testicle it 



|S'; ' begins to manifest its peculiar charac- 



Si:: .::v; ., - ... L.\ \ teristics by the seventh or eighth week, 



\^^ -wx-;^^. ;j|^ ^^ when the germ-epithelium has attained 



considerable thickness, and forms a 

 decided prominence on the mesial side 

 of the Wolffian body. The farther de- 

 velopment of the glandular part of the organ consists mainly in the 

 formation of ovigerms and ova, and the implantation of these in 

 Graafian follicles by a peculiar combination or intermixture of the 

 superficial germinal cells with the deeper blastema which forms the 

 stroma of the organ. 



In a former part of this volume, imder Ovary, p. 478, the development of the 

 primordial ova from a certain number cf the cells of the germ-epithelium and 

 their enclosure in Graafian follicles by the growing stroma of the ovary have 

 been described according to the most recent obsen'ations of "Waldeyer, Kolliker 

 and J. Foulis. The publication of the very careful researches of the last observer 

 enables us to add some important details to the previous description. 



Figure 611, copied from some of Foulis's plates (Trans. Roy. Soc, Edin., 1875) 

 will best show what from these observations appears to be the most j^robable 

 view of the mode of development lof ova in the human ovary. At e, fig. 611. B, 

 is seen a portion of the germ-epithelium, and at c', one of the cells undergoing 

 enlargement and conversion into an ovigerm or primordial ovum. Of this the 

 outer jirotoplasm becomes the yolk, and the nucleus the germinal vesicle with its 

 nucleolus or macula. At o, a single o'S'igerm, and at o\ clusters of ovigerms in 

 various stages of development have sunk into the ovarian stroma, and are being- 

 surrounded collectively and individually by the growth of the connective tissue 

 of the ovarian stroma advancmg from below. Some of the o^^germs in the 

 clusters are more advanced than the rest, and in these, as also in the isolated 

 ovigerm represented in C, a covering of altered connective tissue coi-puscles is 

 seen to be forming round the yolk protoplasm. This is the oi-igin of the cells 

 of the tunica granulosa, which Foulis has shown are not produced, as W^aldeyer 

 believed, from germ-epithelial cells, but from the interstitial connective tissue 

 of the deeper ovarian stroma. In A, o, o, the cell fibres of the stroma («, «,) 

 are seen suiTOunding several individual ova, so as to furnish the first elements 

 of the wall of the Graafian follicles enveloping the ova, and covering imme- 

 diately the granular cells. In D, representing an ovum somewhat farther 

 advanced, the enlarged yolk-protoplasm and the geiininal vesicle are shown 

 entire, with a fragment of the granular cell covering and fibro-cellular wall of 

 the Graafian follicle ; but the zona pellucida is not yet perceptible. 



