MYOLOGY 245 



part of the head (Fig. 90, 12). It is divided into two parts : 

 the interscutellar and the fronto-scutellar. 



The interscutellar is a single muscle, thin and broad, 

 covering the temporal muscle and a portion of the occipital, 

 extending from the scutiform cartilage of the pinna of one 

 side to the same cartilage of the pinna belonging to the side 

 opposite. It approximates the two pinnae to one another 

 by bringing them each into the position of adduction. 



The fronto-scutellar arises from the orbital process of the 

 frontal bone, and from the orbital ligament, which at this 

 level completes the interrupted osseous boundary of the 

 orbital cavity. Thence it is directed, widening as it proceeds, 

 towards the scutiform cartilage, and is there inserted by 

 blending with the corresponding part of the great zygomatic. 

 Its action is analogous to that of the preceding muscle ; but, 

 further, it directs the opening of the pinna forwards. 



These are the muscles which act, for example, when the dog, 

 having his attention strongly attracted by any cause, pricks 

 up his ears and turns the openings forward, in order the better 

 to understand every sound which proceeds, or may possibly 

 proceed, from that which he observes. From this, which 

 may be extremely well seen in some individuals, results the 

 appearance of vertical wrinkles of the skin in the interval 

 between the pinnae of the ears, these being caused by the 

 folding of the integument, whilst the pinnae approach one 

 another. These movements, with which are associated 

 fixation of look and a widening of the palpebral fissure, 

 produce a peculiarly expressive look ; this is why they 

 merit our attention. 



Zygomatico-auricularis (Fig. 90, 11). — Arises from the 

 internal surface of the great zygomatic, passes towards the 

 pinna of the ear, and goes to be inserted into the external 

 part of the base of the pinna, below its opening, to a promin- 

 ence which corresponds to the antitragus of the human ear. 

 It is to this antitragus, but proceeding from another 

 direction, that the parotido-auricular muscle is inserted 

 (Fig. 90, 15). 



With regard to the cervico-auriculars, they are all three 

 present. The superior, or superficial, situated behind the 



