Till-: Ph'LI'IS. 



21 



majority of animals it is more concave from before to behind. The first 

 coccygeal vertehr* are larger and more flexible, and carried at a greater 

 elevation than in the Horse. 



This ditierence of conformation in the pelvis of the Mare is adapted 

 to the passage of the foetus through the canal, and it causes the animal 

 to appear lower in the forehand than the Horse, in which the croup is 

 not so high. It is rare to find a -\Iare which has the croup so square as 

 the Stallion, the hind quarter of which is almost equal in depth, breadth, 

 and length. 



The width of the pelvis of the Mare, as before observed, produces a 

 rocking motion during progression, and this is all the more mai'ked as 

 the animal has been fre(iuently bred from ; for the same reason the 

 speed is not so great, and it has been remarked that Mares which have 

 had several foals are not well adapted for the circus. 



The diflerences in the pelvis of the Mare and the Horse are 

 sometimes noticeable at birth ; but they are generally most apparent 

 when the adult period has been reached, and the body has acquired its 

 definitive form. In both sexes, the supero-inferior diameter of the inlet 

 is greater than the transverse in early life. 



Some idea of the difference in the dimensions of tlie pelvic cavity in 

 the Mare and Horse, may be obtained from the following measurements 

 of two animals about the same in size : 



The differences in the pelvis in the two sexes are, perhaps, not 

 so marked in the smaller domesticated animals until the female has 

 brought forth young several times. 



SECTION IV.— CAPACITY OF THE PELVIS, OR PELVIMETRY. 



We have already casually alluded to the capacity of the pelvic cavity in 

 the largerdomesticated animals, and toitsdiameters; audit will be inferred 

 that these must vary with the different sizes existing in the Mare, Cow, 

 Pig, and Bitch ; though in others which are generally of uniform volume 

 — as the Sheep, Goat, Ass, and Cat — the pelvis does not offer much 

 diversity. In this respect the latter species resemble mankind, in the 

 female of which a difference in size does not make much difference in 

 pelvic dimensions — half an inch probably covering the variations. But 

 in the Mare or Cow, if we compare a small with a large animal, this 

 difference in diameters may extend to nearly two or three inches. 



The subject oi pclvimetrn is very important to the accoucheur of the 

 human species, as the female pelvis is particularly liable to be deformed 

 or defective in its proportions. It is not nearly of so much moment to 

 the veterinary obstetrist, as the head of young animals generally 

 experiences no difficulty in passing through the pelvic cavity, except 



