504 GENCHO FUJIIMURA 



4. The decidual cells {figs. 39 to 71) 



It is a generally well-known fact that decidual cells are divided 

 into very many kinds according to shape, size, staining prop- 

 erties, and structure; however, it has not as yet been definitely 

 decided whether or not these kinds of cells should be reckoned 

 as one and the same sort. Marschand ('04) first divided the 

 decidual cells into two types according to the difference in size. 

 Subsequently, Fraenkel ('14), too, who studied them chiefly 

 from the staining standpoint, set up a similar theory, and tried 

 to divide them into his so-called acid cells (Eckersche Form) 

 and the neutral cells (of large type) ; however, he himself and 

 others had no doubt that there was not only no distinct divis- 

 ion between these two kinds of cells, but rather there was exist- 

 ent an intermediate type of cells between them. 



Figures 39 to 69 illustrate the various kinds of decidual cells 

 placed in order. Of these, cells such as in figure 39 are the smallest 

 and are spherical with a nucleus of a corresponding form. The pro- 

 toplasm is, as compared with the interstitial cells at the time 

 of non-pregnancy, remarkably large in quantity, and contains 

 in it a large number of rod-shaped plastosomes. Figures 40 

 and 41 are a little bit larger than the former, and the one is 

 spherical while the other is oval, both having a nucleus of 

 nearly corresponding shapes. The protoplasm becomes still 

 more abundant and the plastosomes are somewhat longer 

 rods. It is worth our noting that both cells have a kind of 

 boraer membrane already on the superficial layer of the cell 

 bodies. Figure 42 demonstrates the first appearance of a few 

 lipoid granules of various sizes within the cell bodies. Figure 

 43 illustrates a pear-shaped cell, which holds in the body a some- 

 what large quantity of granules and a few vacuoles. A few 

 plastosomes are to be found, and they make their appearance 

 only on one side of the cell. Figure 44 resembles the former 

 in shape somewhat, and contains in the cell body remarkably 

 large lipoid granules, which, on a close examination, are found to 

 have a more or less distinctly clear halo around each of them, as 

 though they constituted the contents of vacuoles. The plas- 



