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 

 different 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 fimbriae, 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 Hned 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 RosenmuUer, 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 

 Girald^s 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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