430 DR MORRISON WA'TSON AND MR ALFRED H, YOUNG 
reflected to the superior wall of the bladder. The diameter of the vagina is 
uniform except at its uterine extremity, where it suddenly contracts to a breadth 
of an inch and a quarter, this contraction indicating externally the position of 
the os uteri in the interior. On slitting open the tube its mucous membrane is 
seen to be thick and of a milk-white colour, and to present different characters 
at different parts of the canal. Corresponding to its posterior fourth the lining 
membrane of thevagina is thrown into a number of longitudinally arranged colossal 
fleshy columns, which, in the second fourth of the canal are replaced by a series 
of very minute folds lying parallel to one another and to the long axis of the 
tube. In the anterior half of the vagina these ruge are, as it were, doubled 
upon themselves at regular intervals, so giving rise to a series of circular valve- 
like folds, the free margins of which present a fringed or puckered appearance, 
and project into the lumen of the canal. Of these circular folds we counted 
eight. The most anterior of them is of larger size than the others, and closely 
surrounds the os uteri. 
The condition of the vaginal mucous membrane above described appears to 
be constant in cetaceans. The number of transverse folds, however, varies in 
different species. HunTER describes two in the porpoise, and states that in 
some species there are as many as nine.* Dr Muriet counted four in Gilobio- — 
cephalus. Both Dr Murte { and Professor TurNER § remark upon the similarity 
in appearance of these folds in Globiocephalus to the margins of the os uteri. 
The same observation holds good of Beluga. 
Uterus and Fallopian Tubes.—The uterus lies between the widely expanded ~ 
peritoneal folds, forming the broad ligament. The corpus uteri measures only 
2 inches in length, its junction with the vagina being clearly indicated externally 
by the constriction before referred to. The os uteri, of very small size, is 
surrounded by the most anterior of the valve-like vaginal folds already referred 
to. Each of the anterior angles of the uterus is prolonged into the correspond- 
ing uterine cornu. The latter, 6 inches in length and 3 of an inch in breadth, 
is flattened from above downward, and diminishing in size at the extremity to 
the thickness of a crow quill, becomes continuous with the Fallopian tube. 
This tube measures 3 inches in length, and continues of uniform diameter as 
far as its extremity, where it suddenly expands into a wide peritoneal infun- 
dibulum, altogether destitute of fimbriz. Connected with each cornu uteri, 
and lying between the layers of the broad ligament, is a number of well-marked 
fibrous cords, which apparently represent the partially obliterated organ of 
tosenmiiller. The mucous membrane of the corpus uteri, as well as of the 
cornua, is thrown into longitudinal folds, which diminish in size toward the 
abdominal opening of the Fallopian tube. A large number of blood-vessels 
* XVI. p. 348. + II. see plate xxxviii. fig. 74. t II. 285, § IX. p. 76. 
