H2 THK I'HYSloI.Or.Y OF REPRODUCTION 



the germinal epithelium. The tubular ingrowths had already been 

 noti dentin, 1 wlin. however, failed to recognise their connection 



tlu" germinal epithelium. Later observers, however, did not 

 : m the tul'tilar origin nf tlie ovary. 



To Wal'levcr U'longs the credit of first recognising the true 

 nature and si_<niticanee <>f tin- process of egg formation, an account of 

 which was published in his famous monograph, Ein-xtiH-k mi<> AV- 

 !! found that in the rhick, on the fourth day of development, the 

 r.el.nuic epithelium which covers the inner surface of the Wolffian 

 body Iwame dihYn-ntiated from the tissue surrounding it, the cells 

 being relathely lai-e and cuhoidal in shape. A little later he 

 observed that tin- cells had multiplied to such an extent as to give 

 rise to a distinct elevation. In this way the germinal epithelium 

 formed, and this marked the site of the future ovary. The 



Fiii. I''!. Sr.-timi through i. vary nf jii<,' rmliryn. (Kroni Williams' 

 i'-.-'. A.ppletoo >v < 



iniiial fjiithclium : S., stroma. 



mesoblast underlying the ^enniiial epithelium is descrihe-d as growini: 

 upwards amon^ the cells of the latter, and so giving rise to the 

 nee of those p-nuinal ingrowths or " e^'-tubes," \\ hich were 

 descril'cil by IMIn_ 



The cells "f the germinal epithelium are thus divided by mesoblast 



into clusters of "egg-nests" which contain tin' primordial ova, as 



\\ al-icyer has .-ho\\n. As a result of this process two zones of tissue 



are formed in the future ovary. The outer or cortical /one consists 



of clusters of cells derived from the germinal epithelium, with 



'bl.istic processes in between them. The' inner or medullary 



is comj>"-''<l at first entirely of -mesobljist. which ^ives rise to 



tsciilar tis-ue and stroma of the ovary. 



The majority of in\ estimators, including l'.altVur, :< Schafer, 4 Xagel, 5 



li- Kntwirki-liin^ del Kolliki-1 in dcin Eieixtxx;ke der 

 < Arc/,., \- 



l."ip/ig, 1X70. 



Ii.-v,-],,|,i,,-i.t cf the Vertebrate Ovaiy," <j,inr. 

 I. xviii., 

 h.- Sim. tun- ..f tlic Iinniatui.' <>\aiian Ovuiii, -tc.." /'/ 



- ' .I,-,-//. /: J///T. .!///., vol. xxxi., 1888. 



