Abdominal Cavity and Uterus. 321 



to be seen, — this was certainly not what had been the zona 

 pellucida,— and the mulberry contained no large cell in its 

 interior — my " queen-bee in the hive." I therefore did not 

 venture to consider it an ovum. (But in 1841 I had the 

 satisfaction to see from Muller's Archiv, that the said inci- 

 dental observation of mine had led to the discovery of rota- 

 tion in what was certainly the mammiferous ovum.*) 



I therefore cannot agree with Keber, that the vesicles in 

 question are ova. What then are they 1 For I am satisfied 

 that he is right in saying — and he was the first to say — they 

 arise in the ovary. I will now mention a few facts that may 

 assist in determining what these vesicles really are. 



Up to 1838 the cavity containing the mammiferous ovum 

 in the ovary was known only as that of the Graafian follicle or 

 Graafian vesicle. In that year - ]" I made known the mode of 

 origin of the Graafian follicle, and in 1841J made several 

 additions which shew how it stands related to a "cell." The 

 Graafian follicle arises in the following way. There is first 

 seen a large cell. The nucleus of this divides into a large 

 number of nuclei, which in colour, form, and size, are exactly 

 like the early state of mammiferous red blood discs. From 

 their origin in a mother- cell, these nuclei after their libera- 

 tion are found in groups. They form cells which are ellipti- 

 cal at first, become more spherical, and sometimes tapered at 

 one end. The number of these cells is countless. But very 

 few of them are matured and make their appearance at the 

 surface of the ovary, though the rudiments of an ovum are 

 seen in all. They are highly elastic, and remarkably trans- 

 parent. They acquire a vascular covering, and there is thus 

 formed a Graafian follicle. Von Baer's " couche interne " 

 of this follicle is the originally independent cell just referred 

 to, and his " couche externe " is the vascular covering which 

 that cell acquires. That cell I found to be common to all 

 the Vertebrata, and in all these to arise, pass through stages, 

 and acquire a vascular covering, in essentially the same way 

 as in Mammalia. There is thus formed the capsule of the 



* Seen in one rabbit by Prof. Bischoff. 

 t Phil. Trans., 1838. J lb., 1841, 



