■60 FEMALE UROGENITAL ORGANS OP PERAMELES, 



portion of the lateral canal into the median vaginal canal. The 

 neck portions of the uteri continue back as described for the 

 virgin, and open eventually into the median vaginal canals. 

 Their lining is greatly folded, and the lumen of each is largely 

 occupied by a cellular detritus. As in the virgin, the posterior 

 portions of the uterine necks and the median vaginse lie 

 imbedded in the connective tissue between the slightly bent upper 

 ends of the lateral vaginal canals. From the anterior ventral 

 end of each median vaginal canal there passes forwards in the 

 connective tissue underlying the uterine necks, the duct-like 

 anterior portion of the lateral canal to open into the corresponding 

 vaginal ctecum. The canals are now very much larger than in 

 the virgin before described, and in one of them pass down the 

 ruptured allantoic stalks to enter the median vaginal canal of 

 "the same side. 



The two median vaginal canals continue on for some distance 

 as laterally compressed canals separated by a common partition 

 wall, the one containing two allantoic stalks and a cellular detritus, 

 the other the detritus alone (Plate v., fig. 10, m.v.c. and a/l.s.). 



Eventually, through the disappearance of the middle portion of 

 the common partition wall, the two canals open into each other. The 

 dorsal and ventral portions of the common wall rapidly diminish 

 in size posteriorly and finally disappear, so that we have eventually 

 in place of two separate canals, a single median canal,— the 

 median vagina, — formed, as we have seen, by the union posterioi-ly 

 of the two vaginal cul-de-sacs. Fig. 11, Plate vi., represents a 

 section through the common median vagina (cm. v.), and in it are 

 plainly visible the sections of the two allantoic stalks (all.s.) 

 surrounded by detritus. Posterior to the level of this section the 

 common median vagina rapidly diminishes in size, it loses its 

 thin muscular layer and finally its epithelial lining disappears on 

 its lower side, thus allowing the two allantoic stalks to come into 

 contact with the surrounding connective tissue (fig. 12, all.s. and 

 ■c.m.v.). As the sections are traced back, the common median 

 vagina disappears completely, and the allantoic stalks are left 

 stranded in what is simply a mere rounded space — the pseudo- 

 vaginal passage, — in the deeply staining dense mass of connective 



