OKCELLA. 401 



I could not detect a bare patch on the pole of the right horn nor on the 

 portion of the chorion which is opposed to the os nteri, but as the chorion opposite 

 the OS was shrivelled, I am not prepared to accept the apparent absence of the 

 bare area as conclusive evidence of its non-existence. But a well-defined patch 

 of that nature occurs opposite the orifice of the left Pallopian tube and on the 

 apical portion of the left horn, corresponding to the middle of the mesial septum, 

 which spot is absent in Platanista, and no such spot is mentioned by Turner in 

 Orca or in the Narwhal. 



On the surface where the vessels enter the chorion, there is a linear bare 

 patch (Plate XXXV, fig. 6), as in P. gangetica, but it is much more limited 

 in its extent than in that genus, being only 6" 50 inches long, with an average 

 breadth of 0""30 ; and that notwithstanding the greater size of the membrane. 

 This area is slightly dilated towards the left of the funis, but no cul de sac 

 exists as in JPlatanisfa. It rapidly contracts on either side of this region, and 

 about V-QO to the right of the funis a pedunculated corpuscle (fig. 6) occurs, 

 as in Platanista. But it is unlike that of Platanista in being slightly swollen at 

 the side of its base next the cord. From the base of the peduncle towards the 

 left side, and traversing the patch throughout its extent, is a narrow linear fold 

 continued to the right of the pedunculated body. 



The bare area corresponding to the left Fallopian tube has a length of 0"'31 

 and a maximum breadth of 0"'18. Only a very minute portion of its dilated part is 

 perfectly smooth, and from it proceed small tliickened folds, two pairs being opposite 

 each other, the remainder of the area being covered with minute papillary folds. 

 The area on the right extremity of the left pole of the chorion is pyramidal in form, 

 and is perfectly smooth, with the exception of a few papillary folds near its apex, 

 from which four larger smooth folds radiate downwards to its base. This pole of the 

 left horn of the chorion is much more villous than the left pole, and hence the bare 

 spots hardly exist in this locality. 



The so-called smooth areas or spots of the chorion are only perfectly smooth 

 in a very limited number of cases, although they may be destitute of villi properly so 

 called, because the non- villous surface is thrown into fine wavy ridges which in some 

 instances occupy the whole of the spot, passing across it in nearly parallel Hues, or in 

 others diving outwards from near its centre in which there is a ridge or fold larger 

 than^ the radial folds. In other cases, however, the centre or a portion of the spot 

 is perfectly smooth, but from its margin fine folds radiate outwards (Plate XXXV, 

 figs. 4 and 5). The villi around these spots are somewhat longer than the others, 

 and hence the chorion presents circular areas of enlarged villi (Plate XXXVII, 

 fig. 14). Besides these areas, there are numerous other long linear dichotomously 

 branched areas of varying extent, very sparsely covered with minute vilh, that, to the 

 unaided eye, appear almost smooth. These do not lie in the course of the chorionic 

 blood-vessels but correspond to the course of the blood-vessels in the uterus. Round 

 non- villous spots may occur along the course of these smooth branched areas. The 

 long linear bare area (Plate XXXV, fig. 6) presents fine outwardly radiating folds 



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