410 HAYATO ARAI 
' D. In this group the follicles show an appearance similar to 
those in Group C, but the outline of the ova shows an irregular 
contour and the nucleus cannot be found. Sometimes we find 
numerous cell contours, devoid of nuclei, which are stained more 
plainly by eosin than normal ova. Whether these numerous 
cell contours were produced from many ova or from degener- 
ated follicle cells which have fallen into the cavity, is not yet 
determined. t 
In the ovary after about sixty to seventy days of age corpora 
lutea are present. These we divided into two groups according 
to their characters, while each of these may be further sub- 
divided into two subgroups. 
A. Large corpora lutea. 1. The corpus luteum which belongs. 
to this subgroup is large in size and its lutein cells show no de- 
generative processes. It contains some blood in its centrum, 
and the lutein cells are full size. 
2. Those belonging to the subgroup (2) show the lutein cells ~ 
less fresh, and signs of degeneration are present. Whether or 
not these two subgroups of large corpora lutea are produced as 
the result of pregnancy, is not clear. 
B. Smail corpora lutea. In this second group the corpora 
lutea are:small and the lutein cells in process of degeneration. 
Among them we can distinguish two forms: B (1) in which the 
corpus luteum is rich in blood capillaries and its lutein cells are 
fresh in appearance while in 
B (2) the lutein cells appear to be resorbed and in their place 
the connective tissue appears, but this form can hardly be dis- 
tinguished from the so-called ‘corpora lutea atresia.’ 
We have counted separately the entire number of normal ova, 
making four groups according to diameter, the degenerate ova 
and the corpora lutea in each ovary—right and left side—and 
finally the total number of ova has been obtained by adding the 
numbers of ova found in both ovaries. 
