RUMINANTIA THE TRUNK. 261 



The Head. 



In the ruminant the palatine ridges being closer together, the pterygoid 

 inuscles originate nearer to the median line of the head, and thus produce more 

 lateral motion in the lower jaw than there is in that of the horse. There is 

 no digastric muscle in the domesticated animals other than the horse, the 

 muscle representing it having only one belly ; in the ox it is joined to its 

 fellow on the other side by a small, square, transverse muscle. The massetcr 

 and temporalis are both less strong. Passing from the root of the horn core to 

 the upper edge of the orbital fossa is a flat thin muscle, the frontalis, which 

 blends with the external levator of the evelid ; it is, perhaps, a portion of the 

 panniculus. The levator labii superioris alceqne nasi is not present in the 

 smaller ruminants, and in the ox it differs in that the anterior, instead of the 

 posterior division, covers the dilatator naris lateralis, and that it covers the 

 nasalis longus as well. Two accessory muscles arise in common with the last 

 named, and go to the upper lip. The dilators of the nostril, except the lateralis, 

 are wanting. The zygomaticus has a long tendon of origin reaching up to the 

 zygoma. The long tendon of insertion of the depressor labii inferioris is wanting. 



The hyoideus magnus has a long tendon of origin, and it forms no sheath, 

 there being no median digastric tendon. The lachrymalis is closely blended 

 above with the anterior border of the orbicularis palpebrarum, and is more 

 developed and thicker than in the horse. 



The Trunk. 



The muscle which would appear to correspond to the sterno-maxillaris of 

 the horse, is considered by Chauveau as representing the inferior fleshy band of 

 the panniculus carnosus ; it is attached superiorly, not to the angle of the 

 maxilla, but to the fascia of the masseter muscle, and sometimes it may be 

 traced to the zygoma. This view being taken, the sterno-maxillaris finds its 

 representative in the sterno-suboccipitalis, a muscle which becomes inserted to 

 the basi-occipital bone in company with a tendon of the levator humeri The 

 sterno-thyro-Tiyoideiis is larger than in the horse, and not digastric. The rectiis 

 capitis a^iticus major is covered by the trachelo-atloideus, a flat muscle joining 

 the atlas inferiorly to some of the succeeding vertebrae. 



The levator humeri is attached anteriorly to the mastoid process, to the 

 posterior surface of the occipital bone and the ligamentum nuchse, to the basi- 

 occipital bone together with the sterno-suboccipitalis, and to the wing of the 

 atlas by a tendon separate from that of the splenius and trachelo-mastoideus. 

 In ruminants the splenius is very .small ; in the camel it is stated by Cuvier to 

 be non-existent, or at least so small as to escape observation. 



In the costal and dorso-lumbar regions there is little that merits comparison ; 

 Ave may, however, note that the trapezius and serratus magnus are largely 

 developed ; also that the intercostales and levatores costarum of course vary 

 in numbei- with the ribs. The pectoralis antictis is small, and blended con- 

 siderably with the transversus. 



The abdominal tunic is large and very thick, its development being always 

 proportional to the magnitude of the abdominal viscera The linem transverse^ 

 'Oi the rectus abdominis are very well marked. The obliquus internus is large. 



