IXTHnXAL nnnAXS nf C t:.\ HIIAT K >\. 



53 



at the rupturetl orifice. In the Cow and Sheep the folUele has a brick- 

 red colour, and in the Pig it is yellowish-brown — it is then designated 

 in the human subject, from its colour, the corpus lutcum ; but gradually 

 the clot shrinks, loses its tint, and the cavity contracts ; at the same 

 time the walls are hypertrophied, and the tunica granulosa becomes 

 wrinkled and transformed into cylindrical epithelium. By the time the 



Fig. 32. 

 Graafian Vesicle and Ovum. 



succeeding ovisac with the ripening ovum has begun to protrude from 

 the surface of the ovary, the old ovisac has lost its colour, with much 

 of its dimensions, and fallen inwards ; the cylindrical epithelium becomes 

 infiltrated with fat and is gradually absorbed. This change, with col- 

 lapse of the wall, depresses the cicatrix of the aperture ; and these suc- 



Fig. 33. 

 KscAPE OK Ovum kuom Ovisac. 



cessive shrinkings and cicatrisations of the ruptured ovisacs give the 

 ovary a pitted and furrowed appearance in advanced life. 



If the expelled ovum be not impregnated, the changes of the ovisac 

 into the yellow convolute cavity, then into the depressed stellate cicatrix, 

 occur somewhat rapidly ; but if impregnation takes place, the matura- 

 tion of successional ova is delayed, and the first change in the ruptured 

 ovisac goes on to a greater extent, the corpus lutcum not becoming 

 obliterated for a comparatively long time. In this period the inner coat, 

 or original ovisac, is much thickened by a larger de^wsit of yellow oil- 

 granules ; it becomes more deeply plicated, is impacted into a yellowish 



