THE I' K LI' IS. I'J 



Sheep and Goat. 



With these animals the pelvis does not differ to any notable extent — 

 except, of course, in size — from that of the Cow. The syviplujiiis is 

 nearly rectilinear in its direction, and its ossification occurs at a very 

 much later period than in the Cow or Mare ; this allows the diameters 

 of the pelvic cavity to be increased during parturition, and accounts for 

 the rarity of ditVicult births in the Sheep and Goat. 



Puj. 



The general conformation of the pelvis in the Pig is not unlike that 

 of Ruminants, except that the sacro-vcrtchral angle, or ' promontory of 

 the sacrum,' is more salient, the canal longer, the ylane of its anterior 

 circumference more oblique, and the direction of the ischio-puhic sym- 

 physis perfectly rectilinear. The pelvic cavity is very large in proportion 

 to the size of the young at birth ; therefore it is that accidents are very 

 rare during the act of parturition. 



BitcJt and Cat. 



In these creatures the sacro-vertcbral angle is still more marked than 

 in the Pig, and diminishes the inlet of the pelvis to a notable extent ; 

 the direction of the symphysis is rectilinear, and the general outline of 

 the pelvic cavity is nearly cylindrical, though the inlet is larger below 

 than above. The ischiii7n, innnediately above the obturator foramen, 

 is wide and shallow, and rises abruptly to almost a right angle ; this is 

 the narrowest part of the canal, and liere it is that the passage of the 

 foetus is obstructed in small females wliich have been impregnated by 

 large dogs. It must be remarked, however, that the late, and often 

 incomplete, ossification of the symphysis allows a certain amount of 

 dilatation of tlie canal, and renders the passage of a comparatively large 

 foetus possible. 



Differences in the Pelvis accokding to Sex. 



There is a considerable difference in the size and conformation of the 

 male and female jjelvis in the domesticated animals, as might be 

 expected from the sexual functions being so diverse in the two creatures, 

 the female pelvis being larger in every sense, but more particularly in 

 its transverse diameter. These differences have only been carefully 

 studied in the Equine species, but they exist in a somewhat similar 

 degree in the pelvis of other species. 



In the Mare, in addition to the pelvis being wider than that of the 

 Horse, the inlet is nmch larger, the ilio-pectineal crests are further 

 apart, and the distance between the lower face of the sacrum and the 

 anterior border of the pubis is much greater, the ilia and pubis being 

 broader and more concave. On the upper surface of the Mare's pelvis, 

 the sacro-sciatic notches are very deep ; the inner border of the ilium 

 forms a very concave line, and the ischiatic spines are widely separated. 

 The tioor of the pelvis is wide, and the bones composing it have a 

 tendency to assume the same horizontal direction. In the Horse, the 

 ischiatic border does not describe a regular curve ; it is composed of 

 two nearly straight portions, which unite where the neck of the ilium 

 begins. The supra-cotyloid crests are not much separated, and are 



