THE ABDOMEN 893 



shaped cells are regarded by some authorities as muscular fibre- 

 cells, but they probably belong to the comiective tissue of the stroma. 

 The stroma is freely permeated by bloodvessels, and contains the 

 Graafian follicles. Immediately within the surface there is a layer 

 of the stroma which presents a granular appearance, especially in 

 young persons, due to the presence of an immense number of 

 Graafian foUicles, with their contained ova, in an early stage. 

 This part of the ovary is called the cortex, the remainder being 

 known as the medulla. Lying more deeply in the stroma there is 

 another set of Graafian foUicles, less numerous, but of larger size, 

 these being in a more advanced stage. Still more deeply there is 



Small Graafian Follicles Mataie Graafian Follicle 



Membiana Grannlosa 

 Discus Proligenis 

 Ovtun 



Ovarian Stroma 



Fig. 375. — Section of the Ovary, showing its Minute Structure. 



another and less numerous set of foUicles, of stiU larger size, which 

 are almost in a state of maturity. When these latter have attained 

 fuU development, they pass towards the surface, where they may 

 sometimes be seen as clear foUicles causing shght projections. 

 When fuUy developed, they attain a diameter of about yV inch. 

 At periodical intervals one or more of these mature foUicles rup- 

 ture, this being accompanied by the discharge of a fluid — the 

 Uquor foUicuh — and the simultaneous escape of the contained ovum 

 or ova. After the discharge of its contents the foUicle becomes 

 fiUed with blood and ceUular tissue, and assumes a yeUow colour. 

 It is then known as a corpus luteum. This undergoes atrophy 

 in the virgin, and, assuming a white colour, is known as a corpus 

 albicans. 



Structure of the Graafian Follicles. — The smaUest foUicles near 

 the surface, which are about yio inch in diameter, consist of a 

 single investing layer of f;ittened ceUs, closely embracing the con- 

 tained ovTim. It is computed that the ovaries of a chUd at birth 



