THE LARYNX 325 



is the smallest of the three sections. It is bounded by the 

 ventricular folds, above, and by the vocal folds below ; it 

 communicates with the vestibule above, and with the inferior 

 compartment of the larynx below. 



Plicae Ventriculares (O.T. false Vocal Cords). The ventri- 

 cular folds are two prominent mucous folds which extend, 

 antero-posteriorly, across the side walls of the laryngeal cavity. 

 They are soft and somewhat flaccid, and their free borders 

 are slightly arched, with the concavities looking downwards. 

 Each fold contains (i) a ventricular ligament; (2) 

 numerous glands, which are aggregated chiefly in its middle 

 part ; and (3) a few muscle fibres. The interval between the 

 ventricular folds is termed the rima vestibuli\ it is consider- 



Base of tongue 



Tubercle 

 Plica vocalis 



Cuneiform tubercle' 



Corniculate tubercle 



Fic. 119. The Larynx as seen in the living person by means of the 

 Laryngoscope. 



ably wider than that between the vocal folds. It follows, 

 therefore, that the four folds are distinctively visible when the 

 cavity of the larynx is examined from above, but the vocal 

 folds alone can be seen when the cavity is examined from below. 

 Plica Vocales (O.T. True Vocal Cords). The vocal folds are 

 placed below the ventricular folds, and extend from the angle 

 between the lamina of the thyreoid cartilage, anteriorly, to the 

 vocal processes of the arytsenoid cartilages, posteriorly. Each 

 vocal fold is sharp and prominent, and its mucous membrane is 

 thin and is firmly bound down to the subjacent vocal ligament. 

 In colour it is pale, almost pearly white, whilst, posteriorly, 

 the point of the vocal process of the arytaenoid cartilage, 

 which stands out in relief, presents a yellowish tinge. In 

 frontal section each vocal fold is somewhat prismatic in form, 

 and the free border looks upwards and medially (Fig. 118). 

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