128 OBSTETRICAL PHYSIOLOGY. 



SECTION II. POSITION OF THE FCETUS IN THE UTERUS. 



The position of tlie fcetus in the uterine cavity is pretty well constant 

 in the same species ; and this position it retains more or less during intra- 

 uterine existence, and until parturition occurs, when it is changed. 



Brugnone, cited by Rainard and Saint-Cyr, writes : " If the uterus of a 

 Mare is opened longitudinally at the ninth or tenth month of gestation, 

 we find the foetus with its head directed backwards, and bent in such a 

 way that its lower jaw touches the throat and its mouth the breast. It 

 forms an arc of a circle ; the neck being in contact with the sacrum, and 

 the spine being bent round is turned towards the right or left side of the 

 lower part of the abdomen. The limbs are flexed : the fore ones in such 

 a manner that the knees reach the middle of the head and the feet the 

 umbilicus ; while the hind limbs are doubled under the abdomen. The 

 croup and haunches are at the bot o i of the uterus, in the vicinity of 

 the stomach." 



Colin states that towards the termination of pregnancy, the fcetus of 

 the Mare lies wifh the belly upwards, the hinder limbs in the longest of 

 the uterine cornua, and the anterior limbs and head directed towards, the 

 cervix uteri. 



In the Cow, according to Saint-Cyr, the uterus is curved downwards, 

 the superior convexity of the body being prolonged forward by the cornu 

 in which the foetus is partially developed. When the uterus is opened, 

 the foetus is discovered with the head bent back, the body much inclined 

 and looking as if almost lying on one side or other, and pressing on the 

 empty cornu, which is considerably less developed than that of the oppo- 

 site side, and which also is lower. Otherwise, like the foal, the calf is 

 curved eii arc, the head more or less near the sternum, and the limbs 

 flexed and close together (Fig. 36). 



According to Colin, the belly of the foetus is downwards in ruminants, 

 and towards the concavity of the cornua, the head being directed back- 

 wards. 



In multiparous animals, the foetuses are distributed in the two cornua, 

 one after the other, the head being usually turned towards the cervix uteri, 

 sometimes to the opposite side, and the abdomen lying towards the con- 

 cave portion of the cornua, where the broad ligaments are attached and 

 the vessels enter. In the Sow, however, it has been noted that the young 

 lie in a contrary direction ; the head, instead of being presented to the 

 cervix uteri, is turned towards the ovarian extremity of the cornua, though 

 the abdomen and limbs always correspond to the concave border of the 

 horns, as it is there the placenta is situated. 



In forty-three Cows and Sheep, Colin found in twenty-five the foetus in 

 the right cornu, and in the left cornu in eighteen. At first sight it might 

 be supposed that the preference for the right cornu was due to the im- 

 pediment offered to development in the left by the large digestive organs 

 of these animals ; but this difference cannot have any influence on the 

 function of the ovaries, the dehiscence of the Graafian vesicles in the 

 right being apparently more frequent than in the left. In multiparous 

 animals, the foetuses are rarely equal in number in both cornua, though 

 neither of the latter has a constant advantage over the other in this re- 

 spect. 



The position of the foetus towards the termination of gestation may 

 vary occasionally, and even frequently, owing to the active reflex move- 



