CHAPTER III 



THE CHANGES THAT OCCUR IN THE NON-PREGNANT 

 UTERUS DURING THE (ESTROUS CYCLE 



" Menstruation is like the red flag outside an auction sale ; it shows that 

 something is going on inside." — Matthews Duncan. 



For full descriptions of the morphology of the uterus in the 



difierent mammahan orders, reference may be made to the 



text-books on human, comparative, and veterinary anatomy. 



But before passing on to describe the changes which occur in 



the histology of the uterus during the menstrual cycle, it may 



not be out of place to remind the reader of the general structural 



relations of the generative organs in the human female. 



The two ovaries, the structure of which is described in the next 



chapter, are situated one on each side of the pelvis, and are 



connected with the posterior layer of the broad hgament of 



the uterus. In connection with each ovary is a Fallopian 



tube or oviduct, which opens into the peritoneal cavity about 



an inch from the ovary.^ Surrounding the orifice is a fringe 



of irregular processes or fimbrise, which, when expanded, assist 



in directing the ovum in its passage into the tube. The tubes 



are about four inches long, and terminate at the superior angles 



of the uterus, with the cavity of which they are in continuation. 



They are surrounded by an external serous coat derived from 



the peritoneum, a muscular coat containing both longitudinal 



and circular fibres, and an internal mucous membrane, which 



is highly vascular and is lined within by a ciliated epithelium. 



^ A vestigial structure lying transversely between the ovary and the 

 Fallopian tube on either side is called the parovarium or epoophoron, or 

 organ of Rosenmiiller, or sometimes the duct of Gartner. It consists of a 

 few scattered tubules, with no aperture. It is the homologue of the epi- 

 didymis of the male. Vestiges of structure corresponding to the organ of 

 Giraldfes are also sometimes found in the vicinity of the parovarium, but 

 nearer to the uterus. These have been called the paroophoron. 



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