CYCLIC CHANGES IN UTERUS AND OVARIES. II 



Mitoses are very rare in the epithelial structures; there may be 

 however a very small number present in the surface epithelium or 

 in the upper gland ducts. Some glands at this period are dilated 

 and filled with polynuclears. Only rarely do we see a mitosis 

 in the connective tissue. We find in some pieces soon after the 

 rupture of the mature follicles hemorrhages beneath the epi- 

 thelium which may raise the surface layer of the epithelium from 

 the underlying connective tissue. 



The same condition we find also in the course of the first day 

 after the rupture of the follicles, at a time, therefore, when 

 connective tissue begins to grow into the follicular cavity. 

 Perhaps the degenerative changes in the surface epithelium are 

 even more marked at this period. 



In four animals in which the ovaries and uterus were examined 

 seventeen and eighteen days after a previous heat, we found 

 ruptured follicles in the animals examined (after seventeen days) 

 or very young corpora lutea (after eighteen days) and the cor- 

 responding condition of the uterine mucosa. 



We may therefore conclude that in animals kept under normal 

 conditions the period of heat occurs approximately every fifteen 

 to nineteen days, a conclusion that is corroborated by other 

 observations which we made. We furthermore conclude that 

 the condition of the uterine surface epithelium indicates in most 

 cases whether or not a rupture of a follicle has taken place in the 

 ovary. 



In a specimen obtained about one to one-and-a-half days 

 after spontaneous ovulation, in which no copulation had taken 

 place, there were present at most places high cylindrical epi- 

 thelium of the surface; at some places, however, the epithelium 

 was somewhat lower; gland fundi show as usual lower epithelium. 

 In the surface epithelium and in the gland ducts with higher 

 epithelium there are mitoses present. The mucosa is rich in 

 cells; is partly a little edematous; there is no increase in the size 

 of the mucosa visible and no mitoses are seen. Some poly- 

 nuclear leucocytes are present in the mucosa, connective tissue 

 as well as glands, although no spermatozoa had entered the 

 uterus; but the number of leucocytes is much smaller than in 

 cases in which copulation had taken place. 



