BY JAS. P. HILL. 65 



invaded by ingrowths of the latter. Posteriorly the passage 

 appears as a long, narrow, empty cleft. In this specimen the 

 cleft can be traced back into the fold separating the openings of 

 the lateral canals into the sinus, but it fades away without 

 reaching the lining of the latter. No trace of the opening into 

 the sinus is perceptible. 



vi. P. aasuta (?) ; no history, but from the condition of the 

 genital organs evidently a multipara. 



As is usual in multiparous specimens, the two median vaginal 

 canals unite posteriorly to form a short common canal (fig. 18, 

 c.Tin.v ) which ends somewhat abruptly. In the connective tissue, 

 just behind its posterior end, appears the remnant of an allantoic 

 stalk. Posteriorly the pseudo-vaginal passage becomes patent as 

 a slit-like space containing dorsally small discontinuous fragments 

 of stalks. 8till further back there appears in the ventral corner 

 of the passage a portion of another allantoic stalk which presents 

 in section the markedly fibrosed appearance shown in fig. 19, 

 Plate ix. This stalk measures in diameter -18 mm. by -12 mm. 

 and extends through about sixty sections. In this stalk the con- 

 centric arrangement of certain of the connective tissue corpuscles 

 is well shown. It is probable that this fibrosed stalk belongs to 

 a later parturition than the fragmentary and small remnants 

 •of stalks occupying the dorsal part of the passage. After the 

 appearance of this stalk, the dorsal half of the passage becomes 

 separated off from the ventral and ends blindly, while the latter 

 continues on as a narrow slit in which other fragmentary portions 

 of stalks appear (fig. 20). In this specimen, also, the pseudo- 

 vaginal passage can be traced almost up to the point of opening 

 of the lateral canals into the urogenital sinus. 



•'»'■ 



vii. P. nasuta, with an early blastocyst in one of the uteri. 

 (Stage A of previous paper). 



This specimen had borne young on at least one previous occa- 

 sion. The two median vaginal canals unite posteriorly to form a 

 single median common canal in the usual fashion in multipara. 

 5 



