MUSCULAR SYSTEM. 85 



larly their seat of action, in order to produce the same effects 

 on the concha, the aid of others will be required, next to be 

 described. 



2. — MuscuLi Proprii Concha. 



These muscles attach the triangular cartilage to the concha. 



Anterior Conchjs — Scuto-auricularis Eiteiuus. 



Situation. — Antero-internal side of the root of the ear- 

 Form. — Two short, thin, narrow fleshy slips. 

 Attachment. — To the outer side and posterior angle of the tri- 

 angular cartilage, and to the antero-internal part of the concha. 

 Relations. — Externally, skin ; internally, cartilage of the ear. 

 Direction. — From behind, forwards; and from within, outwards. 



Posterior ConchjE — Scnto- auricular is Internus. 



Situation. — Deep-seated, at the inner side of the root of the ear. 



Form. — Two fleshy bands, thicker than the last described. 



Attachment. — To the inner side of the triangular cartilage; to 

 the superior angle of the same ; and to the posterior part of the 

 root of the concha. 



Direction. — Downwards, backwards, and outwards. 



Structure. — Fleshy ; the larger slip only possessing a few ten- 

 dinous fibres at its conchal attachment. 



Action of the Musculi Concha:.— The anterior muscle will as- 

 sist in the erection of the ear ; and present the aperture forwards, 

 by drawing round the concha and maintaining it against the tri- 

 angular cartilage. The posterior muscle will have directly the 

 reverse operation : it will rotate the ear the contrary way ; so that 

 the aperture may look backwards and collect sounds from the 

 rear. 



3. RETRAHENTES AUREM. 



Cervico-auriciilares, Externus et Internus. 



Situation. — Behind the ear, upon the side of the poll. 



Form. — Broad, thin, membraniform. 



Attachment. — Posteriorly, to the vertex, ligamentum nuchas, 

 and obliquus capitis superior. Anteriorly, the external portion 

 is attached to the dorsum conchae, about one-third of its extent, 

 upwards : the internal portion, to the root of the concha, and to 

 the annular cartilage. 



Action. — To retract the ear; to draw it down upon the poll ; 

 also to rotate the car, turning the hollow part backwards. 



