THE EAR. 421 



Caudad of this, especially of its proximal portion, are one 

 or two small bands of fibres usually running parallel with it, 

 but unconnected with it and with each other. The extent and 

 distribution of these bands varies, and the direction of fibres is 

 also variable. 



Relations. — Outer surface with the integument; inner sur- 

 face with the auricular cartilage. 



Action. — Flexes the auricular cartilage. 



M. helicis (Fig. 169, 3; Fig. 64, ;;/). — A muscle about 

 two centimeters in length and five or six millimeters in width, 

 on the inner surface of the ear, along its cranial margin. 



Origin on the medial surface of the concha, just caudad of 

 the proximal end of the tragus. The fibres pass distad to be 

 inserted on the auricular cartilage at the caudal angle of the 

 notch which lies beneath the cranial edge of the auricle, along 

 with the caudal fibres of the adductor auris superior (l). 



Relations. — Lateral surface with the integument; medial 

 surface with the tragus. 



Action. — Draws proximad the cranial margin of the auricle. 



M. antitragicus (Fig. 169. 6; Fig. 64, n). — A small muscle 

 about one centimeter in length and three millimeters in thick- 

 ness, attached at one end to the caudal border of the anti- 

 tragus. The fibres pass mediodistad and are inserted on the 

 tragus, in common with the fibres of the tragicus medialis 

 (Fig. 169. 5,5). 



Relations. — Outer surface with the adductor auris inferior 

 and the integument; inner surface with the cartilage. 



Action. — Constricts the external auditory opening. 



M. tragicus medialis (Fig. 169, 5,5'). — A small, flat mus- 

 cle, in two parts, on the medial surface of the concha. 



Origin on the ventral end of the tragus. The cranial 

 fibres form a thick nearly cylindrical bundle which extends 

 proximad about one centimeter, and is inserted on the cranial 

 surface of the concha just proximad of a deep fold in the carti- 

 lage. The caudal fibres form a thin sheet which spreads on 

 the medial surface of the concha and is inserted on an obliquely 

 proximodistal line on the medial surface of the concha, less 

 than one centimeter from the free distal edge. 



