ON THE ANATOMY OF THE NORTHERN BELUGA. 431 
pass forward between the edges of the broad ligament, to be distributed to the 
uterine horns. 
In certain cetaceans there appears to be no separation between the uterus 
and vagina, the difficulty of deciding where the one ends and the other begins 
being attributable to the absence of an os uteri. This condition has been 
noticed by JAckson* in the sperm whale, and by Hountert in Hyperoodon. 
The latter author says {—“ From the last projecting part” (7.¢., the highest of 
the transverse vaginal folds above described) “‘the passage is continued up to 
the opening of the two horns, and the inner surface of this last part is thrown 
into longitudinal rugee, which are continued into the horns. Whether this last 
part is to be reckoned common uterus or vagina, and that the last valvular part 
is to be considered as os tince, I do not know; but from its having the longi- 
tudinal rugz, I am inclined to think it is uterus, this structure appearing to 
be intended for distinction.” There is no doubt of the correctness of HUNTER’s 
conclusions when the uterus of either Globiocephalus or of Beluga, in both of 
which there is a clearly defined os uteri, is examined. At the same time that a 
transverse fold similar to those found in the vagina may occur in the body of 
the uterus itself, is proved by Dr Murin’s§ observation on Gilobiocephalus, and 
justifies the difficulty which even Jonn HunTER experienced in fixing the limit 
between the two organs. The corpus uteri, when it can be clearly defined, is 
uniformly of small size in the cetacea. 
The Fallopian tubes in Beluga resemble closely those of Myperoodon. 
Hunter || describes them in the latter as being remarkably small close to the 
uterus, but expanding gradually to their abdominal extremities, so that they 
resemble a French horn,—a description, the accuracy of which is shown by the 
accompanying drawing of the female organs in Beluga. Dr Murie 4 refers to 
the presence of fimbriz at the extremity of the Fallopian tube in Gilobdio- 
cephalus. Beluga is destitute of such. 
Ovary —Of large size, and of an elongated oval form, the ovary measures 
24 inches in length and ? of an inch in breadth. It presents the appearance 
of being rolled upon itself round its transverse axis, the convex surface of the 
organ being directed upward and lying in contact with the superior layer of the 
ligamentum latum uteri. Its surface is thrown into five or six parallel longi- 
tudinal ridges which extend from end to end of the organ. A number of 
Opaque fibrous cords radiate outward from the outer extremity of the ovary, 
lying between the layers of the broad ligament of the uterus. The exact nature 
of these is open to discussion. In addition to them, another series of obliterated 
tubules, before referred to, pass off from the anterior border of the organ, and 
* IV. p. 145. + XXII. p. 112. t XVI. p. 348, 
§ IL p. 285. || XVI p. 349. q IL. p. 285. 
