ANATOMY OF THE PINNA. 507 



fleshy portion of the pinna, is the lobidus. The space between the 

 helix and antihelix is named the fossa innominata. Another depres- 

 sion is observed at the upper extremity of the antihelix, which bifur- 

 cates and leaves a triangular space between its branches called the 

 scaphoid fossa ; and the large central space to which all the channels 

 converge is the concfia, which opens directly into the meatus. 



The pinna is composed of integument, fibro-cartilage, ligaments, and 

 muscles. 



The Integument is thin, contains an abundance of sebaceous follicles, 

 and is closely connected with the fibro-cartilage. 



The Fibro-cartilage gives form to the pinna, and is folded so as to 

 produce the various convexities and grooves which have been described 

 upon its surface. The helix commences in the concha, and partially di- 

 vides that cavity into two parts ; on its anterior border is a tubercle for 

 the attachment of the attrahens aurem muscle, and a little above this a 

 small vertical fissure, the fissure of the helix. The termination of the 

 helix and antihelix forms a lengthened process, the processus caudatus, 

 which is separated from the concha by an extensive fissure. Upon 

 the anterior surface of the tragus is another fissure, the fissure of the 

 tragus, and in the lobulus the fibro-cartilage is wholly deficient. The 

 fibro-cartilage of the meatus, at the upper and anterior part of the 

 cylinder, is divided from the concha by a fissure which is closed in the 

 entire ear by ligamentous fibres ; it is firmly attached at its termina- 

 tion to the processus auditorius. 



The Ligaments of the external ear are those which attach the pinna 

 to the side of the head, viz. the anterior, posterior, and ligament of 

 the tragus ; and those of the fibre-cartilage which serve to preserve its 

 folds and connect the opposite margins of the fissures. The latter are 

 two in number, the ligament between the concha and the processus 

 caudatus, and the broad ligament which extends from the upper mar- 

 gin of the fibro-cartilage of the tragus to the helix, and completes the 



The proper Muscles of the pinna are the 



Major helicis, 

 Minor helicis, 

 Tragicus, 

 Antitragicus, 

 Transversus auriculae. 



The Major Itelicis is a narrow band of muscular fibres situated upon 

 the anterior border of the helix, just above the tragus. 



The Minor helicis is placed upon the posterior border of the helix, 

 at its commencement in the fossa of the concha. 



The Tragicus is a thin quadrilateral layer of muscular fibres, situated 

 upon the tragus. 



The Antitragicus arises from the antitragus, and is inserted into the 

 posterior extremity, or processus caudatus of the helix. 



