GESTATION. 125 



terfere with parturition. We have already alluded to the sensitiveness of 

 the cervix. The cornua, also, in becoming wider lose their inferior and 

 posterior curves. 



Situation. 



The uterus cannot change its form and volume without altering its 

 situation. Before, and until a certain time after conception, the body of 

 the uterus is contained in the pelvis, but as it and the fcetus increase the 

 position changes, and this causes an alteration in the situation of other 

 organs. In the Mare it gradually displaces the pelvic flexure of the colon 

 lodged in that cavity, and passes forward below that intestine, towards 

 and beyond the umbilicus, to rest on the floor of the abdomen, in proximity 

 to the diaphragm, stomach, and liver, towards the termination of preg- 

 nancy. In its development it is situated chiefly in the middle line of the 

 body, slightly inclining to the left, because of the large mass of the colon 

 occupying the right flank. 



In Ruminants, the uterus pushes the rumen and csecum out of the 

 pelvis, presses the mass of intestines to one side, and extends between the 

 right sac of the rumen and the abdominal walls. The presence of the 

 rumen in the left flank causes it to deviate somewhat to the right. 



In multiparous animals, in which the young are placed end to end in the 

 cornua, the latter rest on each side of the floor of the abdomen and curve 

 upwards ; in the Pig they incline somewhat to the right side, though in 

 both each cornu lies above its corresponding mammary line. 



While these changes are taking place, the broad or lateral ligaments are 

 faciliating them by becoming unfolded and lengthened, and the uterus in 

 its increasing bulk extends backwards as well as forwards. The cervix, 

 firm and resisting, approaches the vulva, and to such a degree sometimes 

 that, in certain breeds of cattle — particularly those which have the pelvis 

 wide and inclined posteriorly, and bear large calves — the posterior por- 

 tion of the vagina appears between the labia of the vulva a month or 

 more before parturition, and especially when they lie down. 



With other Cows, however, whose abdomen is very pendent, the op- 

 posite occurs ; for the uterus, in passing forwards and downwards, carries 

 the posterior portion of the vagina behind it, and this cavity becomes 

 lengthened and constricted posteriorly, while the cervix is shortened, and 

 the vulva appears to be deeply buried between the tuberosities of the 

 ischium. 



Direction. 



With regard to the direction of the uterus, it is to be noted that its hori- 

 zontal position in the domesticated animals obviates those lateral dis- 

 placements which are so frequent in woman, its weight and that of its 

 contents maintaining it in an antero-posterior direction, and in a line with 

 the body of the animal. This direction rarely varies to any appreciable 

 degree, and it is only in a case of hernia at the flank, which is very un- 

 common, that it inclines to one side. The only marked inclination it 

 assumes is forward and downward in Cows whose abdomen is very wide 

 and pendulous. Otherwise, the uterus keeps its normal direction. 

 Rainard draws attention to a form of abdominal hernia which gives the 

 uterus a particular direction ; it is that which takes place in the Mare or 

 Cow, in the vicinity of the crural arch, when the uterus, or one of its 

 horns containing the. foetus, descends behind the corresponding mammary 



