134 



THE EXTERIOR OF THE HORSE. 



by the approximation of its two sides, so as to become A'OB', the 

 results are as follows (Fig. 40) : 



The apparent length of the croup, A'', will be diminished, although the 

 dimension of the levers OA' and OB' do not change. The distance between the 



point of the ischium and the tibia becomes 

 longer. 



The coxo-femoral angle, A'OD, being 

 larger, the impulsive force of the femur 

 will be reduced, because it is transmitted 

 too vertically. This is the principal dis- 

 advantage of this conformation. 



The fixation of the dorso-lumbar spine 

 is easy and powerful, on account of the 

 greater obliquity of the ilium and the per- 

 pendicular incidence of insertion of the 

 gluteal muscles, A'C* 



Such a croup appears short and 

 poorly defined ; the animal lacks mo- 

 bility and develops a vertical im- 

 pulsion ; the region possesses great 

 strength, and he is well fitted to exe- 

 cute the gallop or leap, on account of 

 FIG. 40. the length of the buttock, but he is 



without great speed. We have known 



many horses whose croup had these characteristics, and which per- 

 formed ordinary work satisfactorily. 



In the opposite conformation, A" OB", the croup will appear longer, but will 

 have a tendency to weakness from the horizontal direction of the ilium. 



The movements of the femur will be more extensive, the angle A // OD being 

 smaller. 



The impulsion will be better transmitted than in the preceding case. 



Finally, the buttock will be shorter. 



Feebleness of the croup and loins, greater propulsion from behind, 

 and little aptitude for the gallop and for leaping are the principal 

 characteristics of this form. The gait will lack neither amplitude 

 nor grace, but the weight on the back must be reduced to a minimum. 

 The subject will perform good service as a carriage-horse or for light 

 traction. 



An interesting remark to be made in passing is, that in the three 

 varieties, AB, A'B 1 ', A"B h ', the general direction of the croup is not 

 sensibly modified, while the conditions of force, strength, and speed 

 are all of different orders. We shall return to this point later. 



6. INFLUENCE OF THE MISPLACEMENT OF THE COX^E AS A 



