242 THE ARTISTIC ANATOMY OF ANIMALS 



of maxillo-labialis (Fig. 91, 10 ; Fig. 92) and depressor of the 

 lower lip, is clearly distinct from the buccinator, especially 

 in the horse. It arises, behind, with the deep layer of the 

 muscle to which it is annexed, from the anterior border of 

 the ramus of the lower jaw ; in front it terminates in the 

 thickness of the lower lip. 



In the ox, it is more intimately united with the buccinator. 



It depresses the lip to which it is attached, and displaces 

 it laterally when it acts on one side only. 



In the human species, the pinna of the ear being generally 

 immobile, the muscles which belong to it are, very naturally, 

 considerably atrophied. Accordingly, the auricular muscles, 

 anterior, superior, and posterior, are reduced to pale and 

 thin fleshy lamellse, whose action is revealed in certain 

 individuals, only in a way which may be said to be abnormal. 



It is not the same in quadrupeds. The pinna of the ear 

 is extremely mobile, and its displacements have a real value 

 from the point of view of physiognomical expression. 

 It is therefore necessary to review the muscles which move 

 this pinna without giving them, at the same time, more 

 importance than they merit, since in themselves they do not 

 determine the formation of surface reliefs, which are suffi- 

 ciently apparent. 



Notwithstanding that for certain of these muscles it is 

 possible to trace their analogy with those of the auricular 

 region of man, it is very difficult, because of their complexity, 

 to trace this analogy for all. This is why we shall not be 

 able here, as we have done for the other muscles of the 

 subcutaneous layer, to give at the head of each paragraph 

 the name of a human muscle, and then to group in the same 

 paragraph the muscles which correspond to it in different 

 quadrupeds. Therefore the nomenclature and the divisions 

 adopted for these latter must serve us as a base or starting- 

 point. 



Because the pinna of the horse's ear is so very mobile, we 

 will first begin with a study of its auricular muscles. 



Zygomatico-auricularis (Fig. 92, 11). — This muscle, which 

 is formed of two small bands of fleshy fibres, arises from the 

 zygomatic arch in blending with the orbicular muscle of the 



