ON THE ARRANGEMENT OF THE ECETAL MEMBRANES IN THE CETACEA. 473 



some of which were larger than the great splanchnic nerve in man, accompa- 

 nied the arteries in their distribution. 



When the uterine cornua were opened into, their walls were seen to be not 

 more than from ^ to \ an inch in thickness ; their cavities contained the bag of 

 foetal membranes, and in that part of the bag which lay in the left cornu a good 

 sized foetus had formed. The foetal membranes had become detached from the 

 uterine mucous surface, and could be readily drawn out of the uterine cavity. 

 The two cornua did not communicate with each other so freely in the corpus 

 uteri as might have been supposed from the external examination of that 

 part ; for a vertical fold of mucous membrane, 8 inches in length, the posterior 

 border of which was sickle-shaped and free, formed a mesial septum between 

 the two horns at the anterior part of the corpus ; and the orifice of communi- 

 cation between them, which was situated in immediate relation to the os uteri 

 internum, was not more than about 5 inches in diameter. 



The mucous lining of the cornua had a reddish-brown colour. Its general 

 characters did not quite correspond on the two sides. In the right smaller 

 cornu the mucous membrane, near the funnel-shaped passage into the Fallopian 

 tube was elevated into strong succulent folds, which projected from half-an-inch 

 to an inch beyond the general plane of the mucous membrane. These folds 

 starting from the oviduct, as from a centre, slightly diverged from each other, as 

 they passed parallel to the long axis of the horn towards the corpus uteri, and 

 at the same time gradually subsided, so as almost to have disappeared where 

 the cornu joined the body of the uterus (fig. 1). On closer examination each 

 fold was seen to be subdivided into multitudes of ridgelets, with narrow sepa- 

 rating furrows, which lay almost parallel to each other, and in the direction of 

 the main fold. 



In the large impregnated cornu, the folds were only distinctly visible at the 

 free narrow end of the horn, for they soon subsided to the common plane of 

 the uterine mucous membrane, in all probability owing to the great distension 

 of this cornu. But their original position and direction were marked on the 

 surface of the membrane by parallel lines, which obviously represented the 

 ridgelets previously referred to. 



The vertical fold of mucous membrane, already described as forming an im- 

 perfect mesial septum between the two cornua, was continued along the inferior 

 and superior walls of the corpus uteri, close down to the os internum, and a 

 number of folds of mucous membrane from the inner end of each horn 

 converged to the same orifice. The mucous membrane of the os itself was 

 arranged in distinct and almost parallel laminae, which projected into the cervix 

 uteri. The orifice was filled up with a plug of very viscid and strongly smelling 

 mucus. The lining membrane of the cervix uteri did not show an arbor vitce, but 

 simple longitudinal parallel folds, not so prominent as those of the os internum. 



