THE LARYNX 



1079 



Glossof.pi 'glottic 

 fold 



Ventricular 

 and vocal 

 folds bound- 

 ing ventricle 



Arytenoid 

 cartilage 



Arytcenoideus 

 muscle 



Middle 



cricoihyroid 



ligament 



Fia. 953. Sagittal section of the larynx and upper part of the 

 trachea. 



vocal folds is at first of an elliptical 

 form, but lower down it widens out, 

 assumes a circular form, and is con- 

 tinuous with the tube of the trachea. 

 The entrance of the larynx (Fig. 

 955) is a triangular opening, wide 

 in front, narrow behind, and sloping 

 obliquely downward and backward. 

 It is bounded, in front, by the epi- 

 glottis; behind, by the apices of the 

 arytenoid cartilages, the corniculate 

 cartilages, and the interarytenoid 

 notch; and on either side, by a fold 

 of mucous membrane, enclosing 

 ligamentous and muscular fibers, 

 stretched between the side of the 

 epiglottis and the apex of the aryte- 

 noid cartilage; this is the aryepi- 

 glottic fold, on the posterior part of 

 the margin of which the cuneiform 

 cartilage forms a more or less dis- 

 tinct whitish prominence, the cunei- 

 form tubercle. 



The Ventricular Folds (plicce ventric- 

 ulares; superior or false vocal cords') 

 are two thick folds of mucous membrane, each enclosing a narrow band of fibrous 

 tissue, the ventricular ligament which is attached in front to the angle of the thyroid 



cartilage immediately below the attach- 

 ment of the epiglottis, and behind to the 

 antero-lateral surface of the arytenoid 

 cartilage, a short distance above the vocal 

 process. The lower border of this ligament, 

 enclosed in mucous membrane, forms a 

 free crescentic margin, which constitutes 

 the upper boundary of the ventricle of the 

 larynx. 



The Vocal Folds (plicce vocales; inferior 

 or true vocal cords') are concerned in the 

 production of sound, and enclose two 

 strong bands, named the vocal ligaments 

 (ligamenta vocales; inferior thyroarytenoid) . 

 Each ligament consists of a band of yellow 

 elastic tissue, attached in front to the 

 angle of the thyroid cartilage, and behind 

 to the vocal process of the arytenoid. Its 

 lower border is continuous with the thin 

 lateral part of the conus elasticus. Its 

 upper border forms the lower boundary 

 of the ventricle of the larynx. Laterally, 

 the Vocalis muscle lies parallel with it. 

 It is covered medially by mucous mem- 

 brane, which is extremely thin and closely 



F IG . 954.-Coronal secJion^Maryn* and upper part adherent to itg surface . 



Hyoid bone 



Vocal fold, 



TtiyroarytCB- 



noideus muscle 



