394 



EMBRYOLOGY. 



mesonephric ducts persist even later in a rudimentary condition, and 

 are here known under the name of GARTNER'S canals. 



There are to be distinguished on the degenerating primitive kidney, as 

 in Man, an anterior and a posterior region (WALDEYER). 



The anterior region (figs. 225 ep, 226 ep), or the sexual part of the 

 primitive kidney, which in the male becomes the epididymis, is also 

 retained by the female as an organ without function and here 

 becomes the parovarium (ep), which was first accurately described by 

 KOBELT (the parovarium or epoophoron of WALDEYER). It lies in 



the broad ligament (fig. 226) 

 between ovary (ei) and Miillerian 

 duct (t), and consists of a longitu- 

 dinal canal (ug), the remnant of 

 the upper end of the mesonephric 

 duct, and of ten to fifteen trans- 

 verse tubules (ep). The latter 

 have at first a straight course, 

 but afterwards become tortuous 

 (fig. 227 ep), in much the same 

 way as the canals which in the 

 male are converted into the coni 

 vasculosi. The comparison be- 

 tween parovarium and epididy- 

 mis may be carried still further. 



ei 



Fig. 226. The internal sexual parts of a 

 female human embryo 9 cm. long, after 

 WALDEYER. Magnified 10 diameters. 



ei, Ovary ; t, Miillerian duct or oviduct (Fallo- 

 pian tube) ; t', ostium abdominale tubas ; 

 ep, epoophoron (= epididymis of the male 

 sexual part of the primitive kidney) ; 

 ug, mesonephric duct (vas deferens of the 

 male) ; jpa, paroophoron (paradidymis of 

 the male rudiment of the primitive 

 kidney) ; mk, Malpighian corpuscles. 



As in the male tubules grow out 



from the latter into the cortex 

 of the testis and are there diffe- 

 rentiated into the rete testis and 

 the tubuli recti, so there are also 

 canals found in the female which 

 proceed from the parovarium, 



enter the medullary substance of the ovary itself, and form here 

 the previously (p. 381) described medullary cords, which are highly 

 developed in many Mammals. 



The posterior portion of the primitive kidney, which in the male 

 (figs. 221 and 222 pa) furnishes the paradidymis and the vasa 

 aberrantia, degenerates in the female (fig. 225 pa] in a similar 

 manner into the paroophoron, and is still to be recognised for a long 

 time in the human embryo as a yellowish body (fig. 226 pa), which 

 lies media/awards of the epoophoron (ep) in the broad ligament, and 

 is composed of small, tortuous, ciliate tubules (pa) and a few 



