514 GENCHO FUJIMURA 



The series of changes described above have a more or less 

 difference of time between the decidua serotina and the decidua 

 vera, viz., in the former they may be followed up vigorously 

 up to the end of the second month of pregnancy, though in the 

 third month they suddenly decrease, whereas in the latter 

 such changes may be demonstrated even one month later. 



THE HISTOLOGICAL STRUCTURES AND THEIR FUNCTIONAL 

 SIGNIFICANCE (SOME REFLECTIONS ON LITERATURE) 



In the preceding chapter I have given a somewhat minute 

 account of the delicate histological structures of the various 

 important cell groups which exist in the placenta and the de- 

 cidua vera at different periods of pregnancy. Now, on a peru- 

 sal of the observations given therein, it will be found that as 

 components which are common to the various cell groups there 

 are 1) plastosomes, 2) lipoid granules, and 3) vacuoles. As a mat- 

 ter of course the degree of the appearance of the three kinds of 

 components and their distribution in which they are present 

 vary infinitely as the kind of cells differs or according to each 

 individual cell. However, that which exercises the most im- 

 portant influence over the shape and formation of the cell is 

 chiefly the lipoid granules and vacuoles, of which the latter 

 often appear in a very great number and occupy the whole body 

 of the cell, thus giving the cell a highly foamy appearance or 

 a honey comb structure. The cell which has fallen into such high- 

 ly vacuolar formations makes one feel, at a glance, that it has 

 presented a phenomenon of collapse due to the regression of 

 the cell concerned, as some observers are apt to conclude quite 

 hastily. However, as, on a careful examination of it, it is found 

 that, in spite of the high degree of changes shown by the cell, 

 there are demonstrated for the most part within the cell body 

 the plastosomes which are deemed an important active element 

 in the functions, and also in consideration of the normal struc- 

 ture of the nucleus and of the fully stained conditions of the 

 cell body, there is no doubt as to the cells being alive. And even 

 if it should be conceded for a while that the cell having the fully 

 stained vacuoles as described above is the indication of a kind 



