THE VELVIH. 



17 



Differences in otheu Animals. 



Coxc. 



In the Cow the pelvis (Fig. 10) is longer than in the Mare, and less 

 vertical ; the ischio-pubic symphysis is also longer, and, instead of 

 being straight, is very curved, so that the floor of the pelvis is concave 

 in every direction. The ischial arch is more deeply cut at the sym- 

 physis, and the posterior borders of the ischia join at an acute angle or 

 V-shape, the opening being supero-posterior. The external border of 

 these bones is higher, and the sciatic spine or supra-cotyloid crest is 

 thinner and more elevated. So that, altogether, the bony parietes of 

 the Cow's pelvis are more extensive, comparatively speaking, than the 

 Mare's. The sacral surface is more concave, and the sacro-sciatic 

 ligaments longer, tliough narrower. 



The pelvic cavity (Figs. 11, 12) of the Cow is also less wide, when 

 compared with its height. The diameters of the i/i/c^ — which is more 



Fig. 10. 

 Lo.vciTfDiSAL Section ok tiik Cow'.s Pelvis. 



oblique than in the Mare — are very unequal ; the difference between 

 the sacro-pubic and the transverse, according to Saint-Cyr, being one- 

 third (nine and six inches) ; while it is narrower at its lower part, and 

 not so markedly oval as in the Mare. Its sides are also nearly parallel 

 for some distance, so that its sacro-pubic diameter is greater than its 

 transverse ; the difference varying, according to Saint-Cyr's measure- 

 ments, in favour of the first from 3 centimetres (Fig. 12) to 104 centi- 

 metres (Fig. 11). 



The dimensions of the outlet are not so reduced as in the Mare ; they 

 are more equal, and are about those of the transverse diameter of the 

 inlet. It therefore results that the pelvis of the Cow is more cylindrical 

 and less conical than that of the Mare ; but this feature does not render 

 parturition any easier, for tliougli the outlet is a little larger than in 

 the latter animal, yet this advantage is counterbalanced by the length 

 of the pelvic cavity, the greater extent of its bony walls, and the very 

 marked cun-ature of the symphysis. So it is that, while it rarely 

 happens that the Foal experiences any difficulty in passing through the 

 cavitv, once it has fairly cleared the inlet, in the Cow parturition takes 



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