482 



VOICE AND SPEECH. 



but yet leave an opening behind them as well as in front, no 

 second vocal tone is produced by the passage of the air through 

 the posterior opening, but merely a rustling or bubbling sound ; 



FIG. 173. 



FIG. 174. 



FIG. 175. 



FIG. 173. View of the larynx and part of the trachea from behind, with the muscles 

 dissected ; h, the body of the hyoid bone; e, epiglottis; t, the posterior borders of the 

 thyroid cartilage; c, the median ridge of the cricoid; a, upper part of the arytenoid; 

 s, placed on one of the oblique fasciculi of the arytenoid muscle ; b, left posterior 

 crico-arytenoid muscle ; ends of the incomplete cartilaginous rings of the trachea; /, 

 fibrous membrane crossing the back of the trachea; n, muscular fibres exposed in a 

 part ('from Quain's Anatomy). 



FIG. 174. View of the larynx from above. 1, aperture of glottis; 2, arytenoid car- 

 tilages ; 3, vocal cords ; 4, posterior crico-arytenoid muscles ; 5, lateral crico-arytenoid 

 muscle of right side, that of left side removed ; 6, arytenoid muscle ; 7, thyro-aryte- 

 iioid muscle of left side, that of right side removed ; 8, thyroid cartilage ; 9, cricoid 

 cartilage; 13, posterior crico-arytenoid ligament. With the exception of the aryte- 

 noid muscle, this diagram is a copy from Mr. Willis's figure. 



FIG. 175. View of the upper part of the larynx as seen by means of the laryngo- 

 scope during the utterance of a grave note, c, epiglottis ; s, tubercles of the cartilages 

 of Santorini; a, arytenoid cartilages; z, base of the tongue; ph, the posterior wall of 

 the pharynx. 



and the height or pitch of the note produced is the same whe- 

 ther the posterior part of the glottis be open or not, provided 

 the vocal cords maintain the same degree of tension. 



