SUPERIOR FACE OF THE BODY. 137 



demanded of him. How many of his likeness appear on the turf 

 which are capable of astonishing speed for a short distance, but which 

 cannot maintain it when the distance is increased, being overburdened 

 by the weight which they must carry ! 



Let us change the data of this problem. Let us exact from the 

 motor the production of a force of the greatest possible intensity, 

 whether it be for carrying a heavy weight or drawing a heavy load. 

 Upon what will be based the influence of the direction of the croup 

 in such a case ? 



With M. Neumann, 1 we respond that it depends, so to speak, 

 exclusively upon the inclination of the croup and the coxo-femoral 

 structures, or, if it be preferred, the position of the ilium under the 

 dorso-lumbar arch. Here the length of the muscles and the extent of 

 the movements are a secondary consideration ; it suffices to overcome 

 the intensity of the resistance. Consequently, any anatomical disposi- 

 tion whose effect is to furnish to the pieces of the skeleton a part of 

 the effort required from the muscles, or which gives incidences of inser- 

 tion to them more favorable to their contraction, must be regarded as 

 being in conformity with the adaptation of the subject to this variety 

 of labor. 



A strongly-oblique croup, inclined 40 to 45 degrees, with an oblique 

 ilium inclined 45 to 50 degrees, and with a low ischium, will well 

 fulfil these conditions. A large coxo-femoral angle, which will be the 

 consequence, will place the coxae as a strong support underneath the 

 vertebral column and render the muscles able to sustain the latter, even 

 if it be heavily charged. To exact the least speed from such a horse 

 will be in opposition to physiological laws ; he can only employ his 

 force at a slow pace. 



Between these two extremes there are numerous intermediary types, 

 which may, with sufficient ease, be grouped into three categories, as 

 follows : 



1. Saddle-horses, which are obliged to move a more or less heavy 

 weight carried on their back, at a sufficiently great velocity, whether 

 at the trot or the gallop. Those which are destined for the turf should 

 have a croup approaching the horizontal ideal of 25 degrees, but with 

 a more oblique ilium (30 degrees), for the purpose of giving solidity to 

 the structures anterior to it. Trotters 2 are benefited by a somewhat 



1 G. Neumann, loc. cit., p. 527. 



2 In the American trotting-horse the obliquity of the croup is subject to the greatest varia- 

 tion. In some it is horizontal, in others oblique. In the mare Sunol, three year-old, record 

 2.10%, it is extremely oblique. In such cases the mechanical disadvantage is compensated by an 

 excessive length of the ischio-tibial muscles and those of the thigh and leg in general. (Harger.) 



