142 
J. P. HILL AXD CHA8. H. o’dOXOHHUE. 
coiled and form compact elongate masses^ separated from each 
other by narrow strands of connective tissue carrying blood- 
vessels. The lamina of the glands are only occasionally 
patent. The gland epithelium is in active growth, mitoses 
being frequent. 
The connective tissue, especially in the upper third of the 
mucosa, is loose and cedematous in character and has numerous 
leucocytes dispersed through it. Immediately below the 
uterine epithelium is a narrow dense zone. The blood-vessels 
are enlarging, the mucosa being more vascular than in 
Case 2. 
From the foregoing, it is clear that during pro-oestrus the 
uteri as a whole enlarge, the mucosa increases in thickness 
and becomes more vascular, whilst the uterine glands grow 
in length and become markedly coiled. The uterine epithelium 
also thickens. 
OESTRUS. 
Pro-oestrus is followed by cestrus, i. e. the period of desire 
on the part of the female, and although in one case this 
extended over three days, it appears usually to last only for 
one or perhaps two days. As in the higher mammals, it is 
only at this time that coition occurs. Selenka (23, p. 104), 
speaking of Didelphys marsupialis, states that, “die 
Brunst des Weibchens dauert jedesmal nur 3-5 Stundeii ! 
Our records show that whilst in one case ^ ovulation may 
have coincided with oestrus, the latter practically invariably 
precedes the former. We have records of five females in 
which copulation had occurred (in three of them, five days 
previousl}’), whilst ovulation had not yet taken place, as 
shown by examination of the ovaries. Furthermore, we have 
records showing that unsegmented ova were obtained “ from 
the uteri, four (2-celled eggs also present along with 
unsegniented), five, six, seven and eight days after coitus, 
2-celled eggs six and seven days after, 4-ceHed eggs eleven 
^ This case is referred to in detail on p. 149. 
