A portion continuous with the lower side of the antihelix 105 and evaginated toward the temporal region 201 to some extent is called antitragus 110. A portion on the temporal region 201 side opposed to the antitragus 110 and evaginated toward the antitragus 110 to some extent is called tragus 111, and a bottom end portion continuous with the helix 102 is called earlobe 112.

Between the antitragus 110 and the tragus 111, there is an entrance, called external acoustic opening 113a, to the ear canal 113. The ear canal 113 is in communication with the eardrum, the semicircular canal, and the like. A space that is included in the inner space 150 of the auricle 101 and is surrounded by the antihelix 105, the inferior crus of antihelix 107, and the crus helicis 103, that is, a space in front of the cymba conchae 109 is called a cavity of concha 114, which is in communication with the external acoustic opening 113a of the ear canal 113. A U-shaped open space that is included in the inner space 150 and continuous with the lower side of the cavity of concha 114 is called incisura intertragica 115.

The inner space 150 of the auricle 101 includes the cavity of concha 114, the incisura intertragica 115, and a space near the external acoustic opening 113a of the ear canal 113, and further includes the fossa navicularis 104, the antihelix 105, the superior crus of antihelix 106, the inferior crus of antihelix 107, the fossa triangularis 108, the antitragus 110, and a space in front of the tragus 111.

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