THE UTERINE TUBES OR OVIDUCTS 



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mation of new follicles have never been observed in a person more than two 

 years of age. 



When the vesicular ovarian follicles mature, they form little prominences 

 on the exterior of the ovary covered only by a thin layer of condensed fibrous 

 tissue and epithelium. From the earliest infancy, and through the whole 

 fruitful period of life, there appears to be a constant development and matur- 

 ing of ovarian vesicles, with their contained ova. Until the period of puberty, 

 however, the process is comparatively inactive. But, coincident with the 



FIG. 495. Diagrammatic. Representation of a Human Ovum and Its Coverings. 

 (Cunningham.) 



The corona radiata, which completely surrounds the ovum, is represented only in the 

 lower part of the figure. 



1, Corona radiata; 5, vitellus or yolk; 



2, granular layer; 6, germinal vesicle (nucleus); 



3, vitelline membrane; 7, germinal spot (nucleolus); 



4, zona pellucida (oolemma); 8, nuclear membrane. 



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other changes which occur in the body at the time of puberty, the ovaries 

 enlarge and become very vascular, the development of ovarian vesicles is more 

 abundant, the size and degree of development attained by them are greater, 

 and the ova are capable of being fertilized. The follicles receive their 

 nourishment from the surrounding capillaries in the stroma. They are never 

 penetrated by blood vessels, and are never entered by nerve fibers, so far as is 

 known. 



The Uterine Tubes or Oviducts. The uterine tubes are about 10 

 cm. in length and extend between the ovaries and the upper angles of the 

 uterus. At the point of attachment to the uterus each tube is very narrow; 

 but in its course to the ovary it increases to about 3 mm. in thickness. At 



