THE EXTEBNAL EAR. 849 



and deep ; the situation of their point of insertion in the concha also permits 

 their being classed as superior, middle, and inferior. 



The superior, or superficial ceroico-auricularis, closely united to the 

 external temporo-auricularis, and covered by the skin, covers the middle 

 cervico-auricular, and internal temporo-auricular muscles. Attached by its 

 terminal extremity to the middle of the posterior face of the concha, it draws 

 that cartilage backwards and downwards. 



The middle cervico-auricular is, comprised at its origin between the other 

 two, and intimately attached to them, especially the deep one, is in relation 

 with the skin for the greater part of its superficies. Its terminal extremity 

 is very wide and thin, and passes over the upper end of the parotid gland, 

 to be inserted outwardly into the base of the concha, after being slightly 

 insinuated beneath the parotido-auriciilar muscle. This is a rotator muscle, 

 turning the opening of the ear outwards and backwards. 



The inferior, or deep cervico-auricularis, concealed beneath the upper 

 extremity of the parotid, to which it adheres closely, is inserted at the base 

 of the concha. Its action is similar to that of the middle muscle. 



5. Paeotido-aurioulaeis (abducens, or deprimens aurem — Percivall. 

 Fig. 110, 7). — Lying on the external face of the parotid gland, this is a long, 

 thin, ribbon-like band, narrower and thicker at its upper than its under 

 extremity. It arises on the tissue of the gland, and terminates outside 

 the base of the concha, below the inferior commissure formed by the two 

 borders of that cartilage. 



Covered externally by a very thin portion of the cervico-facial cutaneous 

 muscle, the parotido-auricularis is an abductor of the ear, inclining it 

 outwards. 



6. Temporo-atteiculaeis Inteends {attolens posterior — Percivall. Fig. 

 110, 8). — Situated beneath the superficial muscle of this name, and partly 

 covered by the superior cervico-auricularis, this muscle is long and triangular 

 in shape, bright-red in colour, and extending transversely on the surface of 

 the temporalis; it is attached, inwardly, to the sagittal or spur-like ridge of 

 the parietal bones, and outwardly, by means of a small tendon, to the inner 

 side of the concha, within the terminal insertion of the superficial cervico- 

 auricularis. It is an adductor of the ear. 



(In the Ox, this muscle is not covered by the external temporo-auricularis. 

 In the Sheep and Goat, it is placed between the parietal bone and that muscle, 

 and, to reach the concha, it passes beneath the scutiform cartilage.) 

 * 7. Scuto-auriculakis Inteentjs. (Posterior conchce — Percivall. Leyh 

 makes two muscles of it — small and great.) — This is a muscle composed of 

 two short, pale fasciculi, which cross each other very obliquely, are concealed 

 beneath the scutiform cartilage and the scuto-auricularis externus, and lie 

 directly on the adipose cushion of the ear. They arise from the inner face 

 of the scutiform plate, pass backwards, and terminate at the base of the 

 concha, behind the infundibuliform cavity which that cartilage forms at its 

 root. This muscle is antagonistic to the superficial muscle of that name, 

 as it turns the opening of the ear outwards, and even backwards. 



8. Mastoido-aueictjlaeis. — This name is given to a very thin fasciculus 

 lying vertically on the inner side of the cartilage, at the entrance to the ear. 

 Arising from the margin of the auditory external hiatus, and attached to the 

 base of the concha, this little muscle, in contracting, constricts the carti- 

 laginous tube with which it is in contact. 



