3o8 THE HIND LIMB. 



We have seen in Chapter VIII., that for the attainment 

 of high speed, the horse should possess the fullest ability 

 to bend and extend the hind limb. Hence the beauty, 

 in the race-horse, of a " straight dropped " hind leg. As 

 this power chiefly depends on the action of the hock, 

 its further consideration will be deferred, until that joint 

 is specially discussed (p. 313.) 



On pages 189 and 190, we have seen that the desirable 

 proportions of the bones of the limbs are : pelvis, long ; 

 thigh, short ; tibia (from stifle to hock), long ; cannon-bone, 

 short ; and pastern, long. 



The sets of muscles which move the joints of the hind 

 limb, appear to complete their respective actions, in suc- 

 cession, from above downwards, namely : the hip-joint 

 first ; then the stifle ; and, finally, the hock and fetlock ; 

 the former being extended by the muscle which bends the 

 latter. We may infer that, to be effective in the pro- 

 duction of speed, these actions must increase in rapidity 

 in the same order. As the muscles that " start " the 

 weight at each step are those which extend the hip- 

 joint, we must look for, in the cart-horse, special muscular 

 development of the croup and thigh. In the race-horse, 

 however, length and power of the muscles of the gaskin, 

 which cause acceleration of speed at the end of the 

 " stroke," should be particularly sought for. These de- 

 ductions are in accordance with the nature of the con- 

 formation respectively exhibited by horses which are 

 representative types of these two classes. 



The Pelvis. — The principles discussed in Chapter I., 

 regarding the respective working capacities of long and 

 thin muscles, and short and thick muscles, prove, that 

 for speed we require the pelvis to be narrow, when 

 viewed from behind (Fig. 384) ; and for strength, broad 

 (Fig. 335). The pelvis of the weight-carrying hunter 

 (Fig. 385) may be regarded as an intermediate form. 



If we examine Fig. 129, and refer to Chapter IX., we 



