PYOMETRA IN A CAT. 
?93 
The inner walls of the cornua were smooth and glistening but 
there were slightly raised areas, corresponding to the dark ecchy- 
motic spots seen externally. Both tubes and ovaries were appar¬ 
ently normal. Nothing further of note was to be seen in the 
abdominal or the thoracic organs. 
Histological examination.—The vaginal mucosa is every¬ 
where intact and appears to be normal. Just beneath the epithe¬ 
lium there are isolated patches in which the connective tissue 
cells had undergone considerable proliferation. 
The cornua are covered externally by flat epithelium, this be¬ 
comes cuboidal in the vicinity of the white nodules above de¬ 
scribed. These nodules are composed entirely of connective 
tissue moderately rich in cells, having irregular triangular nuclei. 
The nodules have a very scanty blood supply and are intimately 
adherent to the uterine walls. The muscular coat shows here 
and there small aggregations of connective tissue cellsi 
The mucous membrane in some places is represented by one 
layer of cylindrical epithelium, in other parts by a few round 
glands, and corresponding to the dark patches haemorrhages had 
taken place in the stroma of the mucosa. The surface epithelium 
over such areas is raised from the stroma by the blood but is 
everywhere intact. 
One might at first sight be inclined to think that there was at¬ 
rophy of the mucosa but taking into consideration the extreme 
distention of the uterus there was probably no atrophy. 
Sections from the bladder, tubes, ovaries and liver showed the 
structures to be normal. 
The exact cause of the condition in this case cannot be stated 
positively, but the constriction near the vaginal outlet may have 
been the exciting factor. It is interesting to note the slight alter¬ 
ation that has occurred in the vaginal and also in the uterine walls,, 
there being apparently only little increase in the connective tissue 
elements. The fibrous nodules have probably been produced by 
a mild peritonitis set up by the cornua rubbing against neighbor¬ 
ing structures. 
The fact that the surfaces of the cornua on either side of the 
