THE SALIVARY GLANDS. 203 



turns the head and neck ; or, the shoulder still being the fixed point, 

 and both acting, the head is depressed. This muscle is large in the 

 ox. It is united with the rliomhoideus longus (the long rhomboid- 

 shaped muscle), and evidently contributes mateiially to the forma- 

 tion of those sub-cutaneous muscular fibres, whicli are substituted 

 for the proper sub-cutaneous muscle of the neck. Inferiorly it is di- 

 vided into three branches — the one, thin and inferior, goes to the 

 anterior extremity of the sternum ; the second, at the inferior part of 

 the arm, furnishes a tendon, which is inserted with that of the ijector- 

 alis transversus (the transverse muscle of the chest) into the hu- 

 merus ; while the superior division giv^es a strong tendinous expan- 

 sion, which spreads over, and loses itself upon the outer face of the 

 humerus. 



5. The suh-scapulo-hyoidus, (belonging to the substance under- 

 neath the shoulder, and to the hyoid bone,) from the shoulder-blade 

 to the body of the hyoid bone, to drav,^ backward that bone. 



6. The sterno-maxllaris, (belonging to the sternum and the lower 

 jaw,) from the cartilage in front of the chest to the angle of the 

 lower jaw. It is attached to the lower jaw by means of a bifur- 

 cated tendon. The posterior branch is inserted into the masseter 

 muscle, on which it acts as a kind of bridle in the usual process of 

 mastication, and more particularly as tending to limit the lateral 

 and grinding motion of that muscle. The other goes on and attach- 

 es itself to the buccinator muscle, immediately to be described. Thus 

 they act quite as much as muscles of mastication, as thev are con- 

 cerned in the bending of the head, and perhaps more so. The whole 

 muscle may act on the head — the separate poitions of it on the 

 function of mastication. 



7. The stemo-hyoidus, from the sternum to the hyoid bone, and to 

 the thyroid cartilage of the larynx, in order to draw the bone and 

 the cartilage downward and backward. 



8. The masseter, (masticating muscle) covers the greater part of 

 the side of the superior maxillary bone, and is inserted into the rough- 

 ened surface of the angle of the lower jaw bone. 



9. The buccinator (the muscle by which the human being blows 

 the trumpet) extends from the alveolar borders of the upper and 

 under grinders, over the cheeks, and the membrane of the mouth, 

 and to the angle of the mouth. It tightens the membrane of the 

 mouth, and thus principally assists in the disposal of the food in the 

 mouth, and also in retracting the angle of the mouth. 



10. A branch of the os hyoides. 



11. The stylo-maxillaris, from the styloid process of the occipital 

 bone to the angle of the lower jaw, to draw it backward, and to open it. 



12. That portion of the stylo-maxillaris, which is called the digas- 

 tric, is seen here. 



13. The little flat muscle, the stylo-hyoideus, is here represented; 



