MORPHOLOGY OF THE HUMAN UEINOGENITAL TRACT. 351 



This is nifinifestly the level (v. sheet and fig. 90, Keibel) one 

 must compare with the kangaroo and human fretal tracts, as 

 here the ducts are separated and not approximated. 



We have thus at a certain stage of the development of the liuman 

 fait'us, and at a certain level of the foetus, an arrangement of the 

 ureters and urino^enital ducts analogous to what one would 

 expect in the kangaroo if the lateral vaginal canals be really 

 Wolffian and the central Mtillerian. 



This question, however, requires further working out. 



2. IVie microscopical sei'icd sectional anatomy of the genitcd tract 

 in the Rat Kangaroo. — The structure and relations of the parts 

 were very well brought out in one of the specimens by means 

 of serial sections of the entire tract. These were cut with the 

 Cambridge rocking microtome and stained in the usual manner 

 with logwood and eosin. The organs examined were the ovary, 

 tube, cornu, lateral canals, central portion of vagina, urethra, 

 bladder, ureter and intervening tissue, the rectum and anal 

 glands. 



The Ovary. — This measured 5 mm., and was set in the 

 pavilion of the tube like an egg in a cup. Its connective tissue 

 was continuous with that of an attached fimbria. 



The following structures make up the ovary, and need no 

 comment. Tlie germ epitiielium is well marked over the outer 

 surface, except where the tube was attached. Graafian follicles 

 were present in abundance, and with the ordinary mammalian 

 constituents of tunicse fibrosa et propria, menibrana granulosa, 

 with yelk and ovum. One peculiar feature in the ovary was at 

 the hilum, where, amid a group of endotheliomatous cells, a 

 canalicular system lined with epithelial cells was present where 

 the tube grasped the ovary (fig. 35). Careful study of the serial 

 sections seemed to me to show that this was continuous with 

 the epoophoron, and was thus the paroophoron. 



The ovary in this animal thus varies from the human ovum 

 in two remarkable points — viz., 



1. The paroophoron ends in the centre of the ovary near 



the iiilum. 



2. The ovary is inserted in part into the pavilion of the 



tube, like an egg in a cup. 



