REPRODUCTION. 



Reproduction is the function by which the species is preserved; it is 

 accomplished by the organs of generation in the two sexes. Embryology 

 is the science which investigates the successive stages in the development 

 of the embryo. 



GENERATIVE ORGANS OF THE FEMALE. 



The generative organs of the female consist of the ovaries, Fallopian 

 tubes, uterus, and vagina. 



The ovaries are two small, ovoid, flattened bodies, measuring i^ inches 

 in length and f of an inch in width; they are situated in the cavity of the 

 pelvis, and are imbedded in the posterior layer of the broad ligament; attached 

 to the uterus by a round ligament, and to the extremities of the Fallopian tubes 

 by the fimbrise. The ovary consists of an external membrane of fibrous 

 tissue, the cortical portion, in which are embedded the Graafian vesicles, and 

 an internal portion, the stroma, containing blood-vessels. 



The Graafian vesicles are exceedingly numerous, but are situated only in 

 the cortical portion. It is estimated that each ovary contains from 20,000 

 to 40,000 follicles. Although the ovary contains the vesicles from the period 

 of birth, it is only at puberty that they attain their full development. From 

 this time onward to the catamenial period there is a constant growth and 

 maturation of the Graafian vesicles. They consist of an external investment, 

 composed of fibrous tissues and blood-vessels, in the interior of which is a 

 layer of cells forming the membrana granulosa; at its lower portion there is an 

 accumulation of cells, the proligerous disc, in which the ovum is contained. 

 The cavity of the vesicle contains a slightly yellowish alkaline, albuminous 

 fluid. 



The ovum is a globular body, measuring about T |Q of an inch in 

 diameter. It consists of a mass of protoplasmic material cytoplasm, a 

 nucleus or germinal vesicle and a nucleolus or germinal spot. The peripheral 

 portion of the cytoplasm is surrounded by a clear thick membrane the zona 

 pellucida, external to which is a layer of radially placed columnar epithelium 



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