210 DK. JAMES FOULIS. 



form corpuscles in the walls, and belonging to the stroma of 

 the ovary, indent the protoplasm of each young ovum as it lies 

 in its follicle (fig. 6, 7n, m). 



In an empty follicle from which the youug ovum has been 

 removed, these little connective tissue corpuscles appear as 

 minute buds projecting into the cavity of the follicle from its 

 wall. 



In the deeper parts of the ovary numerous young egg- 

 containing follicles are seen. In the youngest follicles but 

 two or three fusiform corpuscles are found in contact with 

 the yelk of the contained ovum. As the follicles increase in 

 size and become older, the number of small corpuscles in 

 contact with the contained ova also increases. In some we 

 find seven or eight, and in still older follicles a perfect wreath 

 of minute corpuscles is formed round the yelk of the young 

 ovum. The oldest follicles are found in the deepest parts of 

 the ovary, and in most of them there is a perfect wreath of 

 minute corpuscles (fig. 12, r) lining the follicle. Now, from 

 these young connective tissue corpuscles in the wall of the 

 young follicles which lie in contact with and indent the yelk 

 of the primordial ova, the corpuscles of the membrana granu- 

 losa are derived. 



In describing the growth of fibre-like bodies in the stroma 

 into connective tissue corpuscles, I stated that the middle 

 parts of such fibres become swollen out, and in the swollen 

 out part a distinct nucleus appears. This nucleus, though 

 at first appearing semisolid, may become distinctly vesicular, 

 and within it a nucleus is afterwards seen. By a careful exa- 

 mination of a whole series of young Graafian follicles, we 

 trace the development of the corpuscles of the membrana 

 granulosa in the following way : — Around the young ovum 

 in each follicle the connective tissue corpuscles increase in 

 number by division. As a single fusiform corpuscle divides, 

 its nucleus appears to commence the division, and each half 

 of the nucleus carries with it a small quantity of the proto- 

 plasm which originally invested the single nucleus. When 

 a little wreath of such corpuscles is formed round the young 

 ovum the nucleus of each copuscle swells out and beomes a 

 distincly vesicular little body, presenting a very fine double 

 contoured wall, around which is a small quantity of proto- 

 plasm. Within the nuleus generally a minute spot is seen. 

 The protoplasm which surrounds the vesicular nuclei acts as 

 a sort of cement substance, holding them together in the 

 form of a capsular membrane round the young ovum. This 

 capsular membrane is the first appearance of the membrana 

 granulosa. 



