162 MYOLOGfY. 



aponeurotic, and is attached to the ligamentum nuchse, while 

 infero-laterally it becomes more fleshy, and is inserted to the 

 anterior portion of the cariniform cartilage ; some describe this 

 portion as a part of the Levator humeri, the panniculus being 

 firmly blended with that muscle inferiorly. The thoracic portion 

 is continuous with the cervical at the sternum, and passes over 

 the front of the shoulder superiorly, covering its external side ; 

 it is attached to the dorsal spines together with the trapezius. 

 The abdominal portion forms a broad oval-shaped fleshy expan- 

 sion, its fibres running from the flank to the shoulder ; it is 

 thick and fleshy behind the arm, where it has a well-marked, 

 flat tendinous attachment to the skin, and below which a ten- 

 dinous expansion penetrates between the chest and the limb, and 

 is attached to the Pectoralis magnus and internal trochanter oi 

 the humerus. Posteriorly, by a strong band, fleshy and apon- 

 eurotic, it reaches the stifle joint and fascia of the thigh } 

 above, it reaches the lumbar and dorsal spines, and below it 

 becomes blended with the abdominal fascia. 



Relation. — It is related externally with the skin ; internally 

 with the superficial layer of muscles. 



Action. — It corrugates the skin, and thus enables the animal 

 to expel insects and irritating bodies, its use being thus protec- 

 tive ; to some extent it also supports and binds down the subja- 

 cent muscles. 



The Head. 



The muscles of this region may be divided into the following 

 groups : — 



Anterior maxillary. 

 Posterior maxillary. 

 Hyoidean. 

 Palpebral. 

 Auricular. 



In addition to these we have the Glossal, Pharyngeal, and 

 Laryngeal groups also associated with the head; the two first of 

 these will be more appropriately described hereafter when treat- 

 ing of the Tongue and Pharynx, and the last along with the 

 Larynx. 



