1210 



EMBRYOLOGY. 



The ovary, thus formed from the genital ridge, consists of a central part of 

 connective tissue covered by a layer or layers of epithelium, the germinal 

 epithelium. Columns of this epithelium, termed egg-tubes, grow down into the 

 stroma, and simultaneously with this an upward growth of the connective tissue 

 takes place between the columns of epithelial cells. It results from this that the 

 columns of cells become enclosed in meshes of connective tissue (Fig. 784). 

 Each egg-tube or nest represents a primitive Graafian follicle, one cell of which 

 becomes enlarged to form the ovum ; the remainder form the epithelium of the 

 follicle. The remains of the germinal epithelium on the surface of the ovary form 

 the permanent epithelial covering of this organ. According to Beard, the primi- 

 tive ova are early set apart during the segmentation of the ovum and migrate into 

 the germinal ridge. 



The testicle is developed in a very similar way to the ovary, but the processes 

 are not so well marked. Like the ovary, in its earliest stages it consists of a 

 central mass of connective tissue covered by germinal epithelium. A downward 

 growth of columns of this epithelium into the central connective tissue takes 

 place. From these the seminiferous tubules are developed and become connected 

 with outgrowths from the Wolffian body, which, as before mentioned, form the 

 rete testis and vasa efferentia. 



With regard to the other parts of the internal female organs, the Fallopian 

 tube, as has been mentioned, is developed from the upper part of the duct of 

 Miiller, while the lower parts of the two ducts approach each other, and, lying 



FIG. 778. Adult ovary, parovarium, and Fallopian tube. (From Farre, after Kobelt.) a, a. EpoiVphoron 

 formed from the upper part of the Wolffian body. b. Remains of the uppermost tubes sometimes forming 

 hydatids. c. Middle set of tubes, d. .^ome lower atrophied tubes, e. Atrophied remains of the Wolflian duct. 

 /. The terminal bulb or hydatid. A. The Fallopian tube, originally the duct of Miiller. i. Hydatid attached 

 to the extremity. I. The ovary. 



side by side, finally coalesce to form the cavity of the uterus and vagina. This 

 coalescence commences in the middle of the genital cord, and corresponds to the 

 body of the uterus. With regard to the further changes in the female organs, the 

 only remains of the Wolffian body in the complete condition are two rudimentary 

 or vestigial structures, which can be found, on careful search, in the broad 

 ligament near the ovary : the parovarium or organ of Rosenmiiller and the 

 epoophoron (Fig. 778). The organ of Rosenmiiller consists of a number of tubes 

 which converge to a transverse portion, the epoophoron, and this is sometimes 

 prolonged into a distinct duct, running transversely, the duct of Gartner, which is 

 much more conspicuous and extends further in some of the lower animals. This, 

 as has been pointed out, is the remains of the Wolffian duct. About the fifth 

 month an annular constriction marks the position of the neck of the uterus, and 

 after the sixth month the walls of the uterus begin to thicken. The round liga- 

 ment is derived from a band containing involuntary muscular fibres, which runs 

 downward from the lower part of the Wolffian body to the groin, and which in 



