198 DK. JAMES FOULIS. 



structure very similar to that of the ovary of the two to 

 three weeks' old kitchen, but we find in the germ epithelium 

 layer very few primordial ova. Many large spherical nuclei, 

 with a thin film of protoplasm round them, are seen among 

 the germ epithelial corpuscles, and the germ epithelial layer 

 itself is much thicker as a stratum all round the ovary. 

 Most of the large egg clusters below it, at this stage of 

 development, are in communication superiorly with the 

 corpuscles of the germ epithelium, and separating these 

 clusters delicate bundles of young connective tissue, made 

 up of minute fusiform corpuscles, may be traced growing up 

 between and around them. In the deeper part or fibro- 

 vascular zone of such a young ovary the stroma is rich in 

 blood-vessels, and numerous young eggs are imbedded in 

 its meshes, but no large eggs, such as we described in the 

 four weeks' old kitten, are found. 



The Human Ovary. 



In section, the ovary of a human foetus of about seven 

 months presents a somewhat triangular form. The ovary 

 is attached to a stalk or peduncle consisting of fibro-vascular 

 tissue, which passes into the ovary at the hilum and from 

 the direct prolongations of which the whole stroma is 

 derived. On examining a thin section of such an ovary 

 under low powers of the microscope, direct prolongations 

 from the stalk are seen proceeding in a radiating manner 

 towards the periphery in all directions, and communciating 

 with each other in such a manner that the whole stroma 

 becomes arranged in the form of a mesh-work consisting of 

 fibro-vascular tissue. In the meshes of this stroma are large 

 and small collections of corpuscles. At the periphery of the 

 organ the meshes are large, and the contained groups of 

 corpuscles are correspondingly large ; but as we pass deeper 

 into the ovary the meshes with the included groups of 

 corpuscles become smaller, till at last we find small meshes 

 containing but one or two large corpuscles. 



The surface of such an ovary is very irregular, presenting 

 numerous small fossae-like grooves and furrows^ seen clearly 

 under a low magnifying power. 



Investing the ovary, and passing round it from one lateral 

 border to the other, is a layer of columnar corpuscles. This 

 layer is the germ epithelium, and as it invests the ovary it 

 dips down into and lines certain tubular structures and 

 tubiform depressions which, when seen in section, appear 

 as passing down from the germ epithelial layer into the 

 substance of the ovary. 



