
IN MAN AND OTHER MAMMALIA. 351 
meshes of vascular connective tissue, in which are enclosed large and small 
groups of corpuscles. 
In the cortical zone such groups of corpuscles are found under the germ 
epithelium all round the ovary, and in many situations they are in connection 
superiorly with the corpuscles of the germ epithelium. At this stage of 
development the germ epithelium cannot be separated by any distinct line of 
demarcation from the masses of corpuscles which are below it, but at a later 
stage the germ epithelium rests on a thin irregular stratum of young tissue. 
This stratum is part of the fibro-vascular stroma of the ovary, and is formed by 
the growth of that tissue round the groups of corpuscles, which at an earlier 
stage of development are found in connection with the germ epithelial corpuscles 
all round the ovary. 
Tracing downwards the bundles of vascular tissue which lie between the 
groups of corpuscles, we come to the fibro-vascular zone of the ovary (fig. 1, 0). 
It must be understood that there is no boundary line between the cortical and 
fibro-vascular zone ; the division is more or less artificial, but it is certain that 
the cortical, and by far the greater part of such a young ovary, consists of 
corpuscles with a few bundles of vascular tissue intermingled, while the deeper 
fibro-vascular zone, as its name implies, consists of very vascular tissue 
arranged in the form of a mesh-work, and in these meshes are included large 
corpuscles in various sized groups. 
In this fibro-vascular zone we find numerous blood-vessels anastomosing 
freely with each other (fig. 5, 4,4); the blood-vessels everywhere lie in the midst 
of bundles of young connective tissue. In the smallest meshes of fibro-vascular 
tissue generally one large corpuscles is found (fig. 5, m). The largest cor- 
puscles consist of a central, large, bright nucleus with a nucleolus ; the nucleus 
presents a sharply-defined double-contoured wall, and is surrounded by a con- 
siderable quantity of protoplasm, in contact with which are several very small 
corpuscles, forming a sort of wreath round the large corpuscle. Immediately 
outside this wreath is the vascular tissue of the stroma. Many of such large 
bodies as are now described lie imbedded throughout the fibro-vascular zone of 
the ovary, especially in its deeper parts; more superficially, many large bodies, 
but generally without the wreath of smaller corpuscles, are found in the meshes 
of the stroma; and as we pass upwards in our examination of the cortical zone, 
we find the fibro-vascular tissue decreases in quantity, but the corpuscles 
become more numerous, though smaller, till we reach the germ epithelial layer, 
which consists entirely of corpuscles. 
From this description of the appearances presented in a section of the 
ovary of a very young fcetal calf, we learn that the greater part of the parenchy- 
matous zone of such a young ovary consists of corpuscles very similar in 
appearance to the corpuscles of the germ epithelium. From the deeper parts 
