THE GENERA TIVE ORGANS. 199 



may be regarded as their specific secretion. They 

 lie imbedded in a peculiar connective-tissue stroma, 

 the interstitial tissue, and in the adult are confined 

 to the peripheral zone. We have, then, in studying 

 the ovary to consider the interstitial tissue, with its 

 blood-vessels ; and the glandular tissue or Graafian 

 follicles. 



On looking at a thin transverse section of the 

 ovary, we see that it presents two indistinctly 

 separated zones ; an inner or central zone, including 

 the ramifications of the larger blood-vessels, and called 

 the medullary portion ; and an outer, denser cortical 

 zone, in which the follicles lie. The interstitial tissue 

 consists, throughout the entire organ, of connective- 

 tissue bundles, which in the medullary portion are 

 somewhat loosely interwoven and associated with 

 elastic fibres and smooth muscle-cells. In the corti- 

 cal zone the muscular elements fail, the connective- 

 tissue bundles are finer, and cross and interlace in 

 all directions, surrounding the follicles, in whose 

 vicinity they are modified so as to form a kind of 

 capsule. Near the surface of the organ the connec- 

 tive-tissue fibres arrange themselves in crossing lay- 

 ers, to form a dense but not distinct sheath, called 

 the albuginea. 



The connective tissue of the ovary, especially in 

 the cortical zone, contains a greater number, and in- 

 deed in some parts seems almost entirely to consist 

 of spindle-shaped, flattened, and irregular branch- 



