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been already described the layer of cells which separates the 

 omphaloideau trophoblast from the muscular coat of the uterus 

 arises by the rapid proliferation of cells lying between the uterine 

 lumen and the fundi of the glands; in the process the latter are 

 pushed back against the circular inuscles where they lie amidst 

 flattened connective tissue (Fig. 1). 



The cells of the capsularis, as we may term, in a strictly phy- 

 siological sense, the layer in question, are large, polyhedral, clo- 

 sely packed, but still separated from one another by a fibrillar 

 inter-cellular substance. Their cytoplasm also shows a fibrillar 

 structure, and both it and the intercellular matrix stain deeply 

 with acid aniline stains. Their nuclei, which are frequently found 

 in a state of mitosis, especially during the earlier part of this 

 period, and of which very often two or three may be seen in 

 each cell area, are large, approaching indeed in size some of the 

 smaller trophoblastic nuclei. In their structure they bear a great 

 resemblance to the latter, (Fig. 18), since in both the nucleoli are 

 large, the coarser chromatin granules grouped round them, but 

 the smaller distributed over the achromatic reticulum. At the same 

 time there is, in my opinion, always a slight, even if only a very 

 slight distinction between the two, the trophoblastic and the ma- 

 ternal nuclei. Whereas, as was mentioned above, the former look 

 rather pale except in those parts where chromatin granules are 

 aggregated round the nucleoli, the latter constantly appear darker, 

 owing firstly to the greater number of chromatin granules pre- 

 sent in them, and secondly to the affinity which the nuclear sap 

 itself possesses for certain stains, notably carmine and haematoxylin. 



But even if it be conceded that these differences are slight and 

 that there is in reality a very considerable resemblance between 

 the nuclei of these two tissues, it still remains true that they differ 

 greatly in their cytoplasm, and in their origin and later history. 



The blood vessels of the capsularis are feebly developed on the 

 anti-mesometric side, but in the upper, or mesometric region a 

 very large system of anastomosing sinuses is formed which, as 

 may be seen in longitudinal horizontal section of the uterus, radiate 



