444 HAYATO ARAI 
The number of these small degenerated follicles in the ovaries 
without corpora lutea lies between 300 and 900, while in the ova- 
ries with corpora lutea their number varies from 600 to 1400. 
It is a remarkable fact that the number of these smali follicles 
is not particularly different in the ovaries of pregnant as com- 
pared with the non-pregnant rats. Often in the ovaries in which 
corpora lutea are not present the small degenerated follicles are 
abundant, as, for instance, in the rat at 110 days, in which the 
number was 1500. Also in the ovaries with corpora lutea the 
number of small degenerated follicles may be very small, as in 
the rat at seventy days, in which it was 300. The average num- 
TABLE 14 
Tabulation of degenerated follicles 
SMALL MIDDLE-SIZED LARGE 
TOTAL NUMBER 
Fourteen cases without corpora lutea 
Sait | 2S cask 6,734 651 460 7,845 
NIG T AE hg oe eid dn), actus Bee 484 46 33 563 
Seventeen cases with corpora lutea 
Sum. 14,280 463 357 5,100 
AW CTA Ch nt is. stag rain ap oseee 840 27 21 888 
bers of the different sized degenerated follicles in all cases are 
shown in table 14. 
Ovulation 
In regard to:the ovulation of mammals, as well as the matura- 
tion of the ova, there are numerous observations. It is generally 
held that the maturation process takes place only as the result 
of a specific stimulus which may follow copulation or the entry 
of the spermatozoon into the oviducts. Yet there are also nu- 
merous observations which show that the maturation process may 
take place independently of any such stimulus. For instance, 
Weil (’73) in the rabbit, Sobotta (95) in the mouse, Tafani (’89) 
