312 HEALTH AND DISEASE 



Cervico-AuriculaPlS. Three muscles are included in this term the 

 superficial, the middle, and the deep. 



Origin. All three arise from the ligamentum nuchae at the summit of 

 the head, where they are placed one upon another. 



Insertion. The superficial cervico-auricularis is inserted into the 

 middle of the inner surface of the concha, the middle one into the outer 

 side of the same cartilage, and the deep one into the posterior aspect of its 

 base. 



Action. To turn the ear so that its opening shall be directed outward 

 or backward. 



Parotido-Auricularis. -A long, thin, ribbon-shaped muscle situated 

 on the external surface of the throat in contact with the parotid gland. 



Origin. From the outer surface of the parotid gland, from which it 

 ascends to be inserted into the outer part of the base of the concha, 

 immediately beneath the opening. 



Action. To abduct or move the ear outward. 



ParietO-Auricularis Interims. A triangular muscle placed beneath 

 the one last described. 



Origin. From the superior part of the parietal crest. 



Insertion. Into the inner side of the base of the conchal cartilage. 



Action. To draw the ear inward towards the centre of the poll. 



ScutO-Auricularis Internus. This muscle is composed of two small 

 divisions, which cross each other somewhat obliquely. 



Origin. From the inner surface of the scutiform cartilage. 



Insertion. Into the posterior part of the base of the concha. 



Action. Assists in directing the opening of the ear outwards, and also 

 backwards when required. 



Mastoido-Aurieularis. A very small muscle, situated at the inner 

 side of the root of the ear. 



Origin. From the margin of the auditory process of the petrous 

 temporal bone. 



Insertion. Into the base of the conchal cartilage. 



Action. Not definitely known. 



The basement cartilages of the ear rest upon a cushion of fat, which 

 facilitates their rapid movement in various directions. 



MUSCLES OF THE HYOID REGION 



Mylo-Hyoid. This muscle is situated beneath the tongue and between 

 the branches of the lower jaw. With its fellow they stretch across from 

 one branch to the other, and support the tongue as in a sling. 



