290 THE MUSCLES. 



The buccinator is very thin, and formed of only one muscular plane. 



The zyijomaticus is continued, superiorly, with the attollens anticus. 



The levator lahii superioris represents a wide, undivided, muscular expansion, united 

 superiorly to the panniculus of the forehead, and terminating inferiorly on the upper lip. 



The levator lahii superioris and dilator naris lateralis constitute a single fleshy body formed 

 of several parallel fasciculi, which take their origin above the supra-orbital foramen, and 

 terminate together at the external wing of the nose and in the upper lip. 



There is no dilator naris superioris, or dilator naris transversalis. 



The middle anterior (depressor alx nasi) is perfectly developed. 



The mento-labialis and its suspensory muscle, the middle posterior, are scarcely apparent. 



2. Palpebral Region. 

 The lachrymalis in the Ox is more developed and thicker than in the Horse. Its most 

 anterior fibres glide under the zygomaticus, and are lost on the surface of the buccinator ; while 



Fig. 172. 



SUPERFICIAL MUSCLES OF THE OX'S HEAD. 



1, Dilator naris superioris ; 1, 1', accessory fasciculi of the same ; 2, dilator naris lateralis ; levator 

 labii superioris ; 4, lachrymalis; 5, depressor labii inferioris ; 6, buccinator confounded with the 

 preceding; 7, zygomatico-labialis; 8, frontal, or cuticularis muscle of the forehead ; 9, orbicular 

 muscle of the eyelids; 10, zygomaticus; 11, attollens maximus; 12, scutiform cartilage; 

 13, external scuto-auricularis ; 14, mastoid process; 15, masseter ; 16, stylo-hyoideus ; 17, 

 digastricus ; 18, sterno-maxillary fasciculus belonging to the cervical panniculus; 19, subscapulo- 

 hyoideus; 20, sterno-maxillaris, or mastoideus; 21, anterior branch of the superficial portion of 

 the mastoido-humeralis ; 22, superior branch of ditto ; 23, deep portion of same muscle ; 24, 

 trachelo-atloideus, peculiar to Ruminants and Pachyderms ; 25, great anterior straight muscle 

 of the head. 



the most posterior pass above the aponeurotic tendon of the zygomaticus and become confounded 

 with tiie panniculus. This muscle unites, above, with the orbicularis palpebrarum in a more 

 intimate manner than in the Horse, so that it is almost impossible to define the limits of the 

 two (Fig. 172, 4). The lachrymalis is absent in the Pig. 



3. Masseteric or Temporo-maxillary Region. 

 In Ruminants, the masseter and temporalis are not so large as in Solipeds. In the 

 Camivora, however, they offer a remarkable development. The origin of the pterygoideus 



