THE URO-GENITAL SYSTEM 391 



longitudinal fold which contains in its margin the Mullerian 

 duct. The germ gland (here the ovary) is attached to this 

 along the inner side of the mesonephros by means of a narrow 

 mesovarium. Imagine now the two important changes which 

 actually occur, namely, the complete reduction of the meso- 

 nephrotic system and the development of the Mullerian duct 

 into oviduct and uterus, and we have as a result the broad 

 ligament, arising from the body wall and extending to the 

 oviduct, which it enwraps along its free edge. The round 

 ligament is formed from the posterior slip of the original meso- 

 nephrotic ligament, the ligamentum ingninale. 



The vestiges of the mesonephrotic system are found ex- 

 actly where they would be expected, lying in the broad liga- 

 ment not far from the oviduct, bet\veen it and the insertion of 

 the mesovarium. They consist of three portions, epoophoron, 

 its longitudinal duct, and paroophoron. [Plate III, cJ] The 

 first of these (" organ of Rosenmiiller ") consists of a series 

 of blind tubules attached to a common duct, and plainly repre- 

 sents the vasa efTerentia and the upper portion of the Wolffian 

 duct, in other words, the " sexual kidney." Below this are a 

 few scattered tubules, forming the paroophoron and represent- 

 ing the lower or urinary portion of the mesonephros. The 

 longitudinal duct of the epoophoron ("Gartner's duct") is 

 the remnant of the main part of the Wolffian duct, and lies 

 imbedded in the wall of the uterus; it occasionally joins its 

 upper part and thus completes the representation of the meso- 

 nephrotic system. It occurs quite regularly in the pig, the 

 horse and in ruminants, but is only occasional in Man. 



The original direction of the mesonephrotic ligament, that 

 is, the direction which it has in the embryo, and that which is 

 retained in adult Sauropsida, becomes changed in mammals 

 and comes to lie transversally across the- dorsal wall as though 

 laid over laterally from above, the lower part remaining as at 

 first. The principal effect of this is to remove the ovaries, 

 and with them the oviducts, from their primary position in 

 the lumbar region and located them near or within the brim 

 of the pelvis, not far from the inguinal region. This occa- 



