62 FEMALE UROGENITAL ORGANS OF PERAMELES, 



Towards the exti'eme posterior end of the common median vagina, 

 just donsal to the deeply staining mass of connective tissue 

 enclosing the pseudo-vaginal passage with its two allantoic stalks, 

 occurs a definite small triangular cleft. This can be traced 

 posteriorly for a considerable distance, when it enlarges and opens 

 into the above-described pseudo-vaginal passage containing the 

 allantoic stalks. This cleft I regard as the pseudo-vaginal passage 

 of a previous parturition, and this view is strengthened by the 

 occurrence just below it of fragments of allantoic stalks incorporated 

 in the connective tissue. These remnants are recognisable by 

 their staining lighter than the surrounding dense connective tissue, 

 by their reticulate fibrous appearance and by the presence in them 

 of small spindle-shaped nuclei showing in places a distinct tendenc}' 

 to concentric arrangement. 



A less altered remnant of a stalk which is not yet so definitely 

 incorporated in the surrounding tissue, also occurs laterally to the 

 pseudo- vaginal passage, and may belong to a later parturition than 

 the above-described remnants. Both sets are traceable throuarh 

 a considerable number of sections. In the description of certain 

 of the remaining specimens, similar persisting remnants of 

 allantoic stalks will be shown to exist, and in such a condition as 

 to necessitate the reforming of the pseudo- vaginal passage, over 

 at least part of its extent, as has apparently been the case in the 

 female under consideration. 



The present specimen, then, shows us that after parturition is 

 Completed, the median vaginal cul-de-sacs open into each other 

 posteriorly to form a short median epithelially lined canal — the 

 common median vagina, — from the end of which there leads away 

 the non-epithelially lined cleft-like pseudo-vaginal passage, in this 

 stage definitely continuous with the common median vagina but 

 with its opening into the urogenital sinus no longer recognisable. 



iii. P. ohesula, with two 22 mm. young in pouch. (Stage F of 



previous paper). 



The genital organs of this specimen have already been described 

 in my previous paper (pp. 431-2), but without figures. For com- 



