418 JAS. P. HILL. 



and attenuated. This is especially noticeable close to the sinus 

 terminalis (fig. 24, bil. omph.). Further out one meets with 

 scattered projecting cells of large size and of irregular form, 

 the protoplasm and nuclei of which stain deeply. 



The entoderm has also become considerably thinner in places. 

 Where it has not undergone attenuation the cell protoplasm is 

 often found to be greatly vacuolated, with irregular deeply 

 staining nuclei. Here and there, also, unaltered entoderm 

 cells are met with either singly or in groups. 



Stage E. — P. nasuta (post-partum). 



The material available for this most important stage con- 

 sisted of the genital organs (less the cloaca) of a female P. 

 nasuta, together with two newly born young from the pouch. 



The new-born young (fig. 36) had a crown-rump measure- 

 ment of 14 mm., and a head length of 6 mm. For the details 

 of their external characters and internal anatomy see table 

 (appendix). 



Both uteri were considerably enlarged : the left, the larger 

 of the two, measured 17 ram. in length by 9 mm. in breadth; 

 the right had a length of 16"5 mm. and a breadth of 8*25 mm. 



When the uteri were opened up it was found that parturi- 

 tion had been recently accomplished, and that in each uterus 

 the flattened vesicular allautois with its stalk attached was still 

 adherent over the placental area (fig. 25, pi. a.). This latter 

 formed a fairly sharply circumscribed ovalish area^ bounded by 

 an almost continuous ridge, and differed from the rest of the 

 irregularly ridged uterine surface by its closer texture. It 

 was situated on the dorso-mesial inner surface of the uterus, 

 i. e. ant-mesometrially. The area measured 9 mm. in length 

 by about 5 mm. in breadth (i.e. without following the folds). 

 The allantoic vessels ramifying in the inner wall of the allan- 

 tois could not, in surface view, be very definitely made out. 

 Apart from the adherent allantois no other portions of the 

 foetal membranes were encountered in the uterus. 



The left uterus alone was submitted to microscopic exami- 

 nation. 



