SECRETORY FUNCTIONS IN HUMAN PLACENTA 543 



and the functions of cells at this period are therefore set aside 

 for future investigations. 



5. The phenomena of secretion in the uterine glandular cells at the 



time of pregnancy 



The epithelium of the uterine gland undergoes a remarkable 

 change in the early part of pregnancy, viz., on about the seven- 

 teenth or eighteenth day after conception (figs. 72 to 83) . Now, 

 if we consider its phenomena of secretion, we shall find that, 

 even in this cell, lipoid granules first appear, and then vacuoles 

 are formed. In the stained preparations, lipoid granules appear 

 assembled and are accumulated especially near the basal part of 

 the cell body and show a remarkably clear yellowish-brown color 

 (figs. 73 to 78) . The latter often appearing as contents of vacuoles 

 (figs. 77 and 78), it would probably appear that the vacuoles are 

 a modified product of the lipoids, just the same as in the other 

 cases. In this way the lipoids gradually change into vacuoles, 

 the cell grows in size and presents a highly honeycomb structure 

 (figs. 77 to 80) . The plastosomes either decrease in quantity or 

 become very difficult to discover as the functions of secretion 

 increase in activity. However, I have not been able to make 

 clear the formative relations between the plastosomes and 

 lipoid granules. Be that as it may, it happens that, with the 

 increase of the function of secretion and the growth of the cells, 

 the latter gradually move over toward the comparatively enlarged 

 glandular lumen, and, at last, leaving the wall of the glandular 

 tubule, are entirely free within the glandular lumen. The 

 characteristics of these desquamated cells are that either 

 the cell body shows a highly vacuolar formation or that the 

 vacuoles being somewhat reduced in quantity, the protoplasm 

 becomes dark and turbid, and no plastosomes are to be found. 

 The condition of the nucleus is also exceedingly abnormal (figs. 

 81 to 83). How the various cells of this kind are broken up 

 by degrees and added to the large quantity of fragments fiUing 

 up the glandular lumen can be observed and followed with a 

 great certainty. 



The various changes of the uterine glandular cells as described 



