
IN MAN AND OTHER MAMMALTA. 373 
meshes of the stroma. At the same time the imbedded corpuscles are developing 
into primordial ova. This intercorpuscular growth of connective tissue takes 
place in all parts of the ovary wherever groups of germ epithelial corpuscles become 
imbedded, and it continues until the inclusion of germ epithelial corpuscles from 
the surface of the ovary has ceased. It is in this way, and in this way only, that 
we have Graafian follicles formed. As already explained, the Graafian follicles 
are the ultimate meshes of the stroma, formed by the growth of the connective 
tissue around the developing primordial ova. As these young ova become 
surrounded by the vascular tissue, the connective tissue corpuscles in the wall 
of the follicles in contact with their yelk develope into the corpuscles of the mem- 
brana granulosa in the manner described. According to my observations, tubular 
structures have no existence in the ovary at any period of its development, 
and I have never detected the formation of Graafian follicles and the corpuscles 
of the membrana granulosa in any other manner than that I have indicated. 
By the continued free growth of the vascular stroma throughout the whole 
organ, the walls of the Graafian follicles become greatly thickened. The oldest 
and largest Graafian follicles are situated in the deepest parts of the stroma; 
this is what we would naturally expect, for they were the first formed, and lie 
surrounded by a great number of blood-vessels which are branches of the 
large trunks entering the ovary at the hilum. 
Thus, in the ovary of a rabbit of about six weeks, one sees the largest 
Graafian follicle situated deeply in the organ; on the surface of the ovary is the 
germ epithelium. Between the deeply situated Graafian follicles and the germ 
epithelium on the surface of the ovary, the Graafian follicles with the contained 
ova become gradually less and less in size. The youngest Graafian follicles, 
the last formed, are found immediately under the layer of tissue known as the 
tunica albuginea on which the germ epithelium rests. 
Although the eggs are so numerous in an ovary at birth, very few of them 
come to maturity. 
In the ovary of a cat about five months old is a thick zone of young eggs 
immediately under that stratum of tissue which passes round the ovary con- 
stituting the tunica albuginea. This egg zone is all that remains of the egg 
clusters which I described as forming so large a part of the ovary of a kitten 
of two to four weeks. . 
Below the egg zone the ovary consists of fibro-vascular tissue. This part 
forms about two-thirds of the whole organ, and thick processes of it pass upwards 
among the eggs in the egg zone. These thick processes have developed from 
the long strings or delicate bundles of fusiform corpuscles, which in the young 
kitten grew up between the egg clusters separating these latter from each other. 
Secondary offshoots may now be traced growing from the larger bundles in 
VOL. XXVIl. PART III. dE 
