50 



OBSTETRICAL ANATOMY. 



layer, the vitcllus or yolh, the larger granules of which are superficial 

 and compact, while internally it is a transparent albuminous fluid, in 

 which are but few granules. Enclosed in this vitellus, though nearer 

 its circumference than centre, is the nucleus— the germinal vesicle, or 



Fig. 27. 



Ovary opened Vertically. 



a, a, b, h, Graafian Vesicles at different 

 stages of development. 



Fig. 28. 



Portion of the Ovary of a Pig. 



a, Point at which a ripe Vesicle is about 

 to escape ; b, Fissure by which an 

 Ovule has escaped. 



vesicle of Purhinje, a most important portion of the ovum ; it has the 

 appearance of a very small clear ring, measuring about l-60th of a line 

 in diameter, and upon its surface is a dark spot, the inacnla germinativa. 

 This is always observed as a simple rounded body, measuring from 



Fig. 29. 



Graafian Vesicle in Make's Ovary. 



a, Membrana Propria of the Graafian 

 Follicle ; b, Membrana Granulosa ; 

 b'. Discus Proligerus ; c, Ovum. 

 Magnified 5 Diameters. 



Fig. 30. 



OVULUM OF THE MaRE. 



, Zona Pellucida ; b, Vitellus, con- 

 taining the Vesicula Germinativa ; 

 c, Cells of the Discus Proligerus. 



l-200th to l-300th of a line in diameter ; it is rarely found double or 

 as an aggregate of granules, except in miniature ova. 



The large flexuous arteries supplying the ovary are from the utero- 

 ovarian trunk; they spread over the spaces in the tunica albuginea, 

 before entering the hilus of the organ to be distributed in its interior. 



