538 GENCHO FUJIMURA 



separately as a small independent 'organel' within the cell, 

 this hypothesis of mine should not be taken exception to. And 

 moreover, the increase and mass of protoplasm or plastosomes 

 and the lipoids at different phases, all of which could be demon- 

 strated in every part of this cell at any time, if sought for an 

 interpretation of their significance, will each provide a mate- 

 rial to substantiate the hypothesis mentioned above. In this 

 manner, this cell, while promoting its secreting functions on 

 one hand, grows in size more and more, and such like rela- 

 tions could be recognized more or less even in the Langhans' 

 cell. 



The functions of secretion in the stroma cells of villi begin 

 at the end of the first month of pregnancy and continue 

 actively until about the seventh month, though they are most 

 active from the second month to the sixth. And though in the 

 eighth month it appears that they suddenly subside, it will be 

 found at all times that it is difficult clearly to follow the 

 destiny of each of the cells, since it is interfered with by the 

 strong increase of the capillary blood vessels of villi at this stage, 

 as mentioned already. Since no special duct was detected, it is 

 difficult to tell how the secretions are removed, other than 

 by attributing it to osmose, as in the case of the Langhans' 

 cells, and by predestining the secretions to be absorbed by 

 the embryo. 



4. The phenomena of internal secretion of decidual cells 



If we first look at the decidual cells of the smaller type (figs. 

 39 to 51), we find that the chief components of the cell body in 

 the youngest are plastosomes (figs. 39 to 41), next appear lipoid 

 granules (figs. 42, 43, and 44), then follow vacuoles, it thus be- 

 ing customary for the great majority of decidual cells of smaller 

 type to contain many vacuoles and more or less lipoids besides 

 plastosomes. The plastosomes sometimes decrease more or 

 less in quantity in inverse ratio to the lipoids or vacuoles (figs. 

 43 and 49), but more often is it difficult to discern such relation, 

 and, besides, many are plastosomes which either form a con- 

 spicuous group in some part of the cell body or considerably 



