518 



STRUCTURE OF THE LARYNX. 



Man. This sound is produced by the apparatus termed the 

 larynx, which is situated beneath the base of the tongue, and 

 in front of the pharynx ( 192, fig. 107). It is suspended, 

 as it were, from the hyoid bone (h, fig. 261), a bone of a 

 horse-shoe form, detached from the rest of the skeleton; 

 from two projections (I) on the upper side of which, several 

 of the muscles of the tongue originate. The sides of the 

 larynx are formed by two large cartilages (t, fig. 261), which 



VERTICAL SECTION op 

 THE LARYNX. 



ar, arytenoid cartilages; 

 v, ventricle of tlie glot- 

 tis ; e, ep : glottis; the 

 other references as be- 

 fore. 



Fig. 263. 



FRONT VIEW OF THE 

 LARYNX. 



The interior wall is mark- 

 ed by the lines a, a,b,b; 

 li, inferior ligaments 

 of the glottis, or vocal 

 cords ; Is, superior liga- 

 ments; the other re- 

 ferences as before. 



tr 



Fig. 261. 



HUMANLARYNX,VIEWED 

 SIDEWAYS. 



h, hyoid bone ; I, point of 

 origin of muscles of the 

 tongue ; t, thyroid car- 

 tilage ; a, projection in 

 front, commonly called 

 Adam's apple ; c,cricoid 

 cartilage ; tr, trachea ; 

 o, posterior side of the 

 larnyx, in contact with 

 the oesophagus. 



are termed the thyroid cartilages ; where these meet on the 

 middle line a projection is formed, which is particularly 

 prominent in Man, and has received the name of Pomum 

 Adami, or Adam's apple (a). The thyroid cartilages rest 

 upon another, termed the cricoid (c); this has the form of a 

 ring, much deeper behind than in front, and surmounts the 

 trachea, with the upper ring of which its lower edge is con- 

 nected by a membrane. Upon the upper surface of the back 

 of the cricoid cartilage, where there is an open space left 

 between the two thyroid cartilages, are mounted two small 

 cartilaginous bodies, the arytenoid (ar, fig. 262). These are 

 movable to a certain extent ; and their position may be 

 changed in various directions by several muscles which act 

 upon them. 



