CAVITY OF THE LAKYNX. 



1069 



Epiglottis 



Hyoid bone 



the arytsenoid cartilages. These small nodules of cartilage raise the dorsal part of 

 the ary-epiglottic fold in ( the form of two rounded eminences, termed respectively 

 the tuberculum cuneiforme [Wrisbergi] and the tuberculum corniculatum [Santorini]. 



On each side of the laryngeal opening there is, in the pharynx, a small recess, 

 directed downwards, which presents a wide entrance, but rapidly narrows towards 

 the bottom. It is termed the recessus piriformis, and is of importance to the surgeon, 

 because foreign bodies introduced into the pharynx are liable to be caught in this 

 little pocket. On the medial side the recessus piriformis is bounded by the 

 arytsenoid cartilage and the ary-epiglottic fold, whilst on the lateral side it is 

 limited by the inner surface of the laminae of the thyreoid cartilage, clothed with 

 the pharyngeal mucous membrane. 



Vestibulum Laryngis. The vestibule of the larynx is the uppermost compart- 

 ment of the cavity of the larynx. It extends from the laryngeal aperture to the 

 ventricular folds. In its inferior part it ex- 

 hibits a marked lateral compression. Its width, 

 therefore, diminishes in the vertical direction, 

 whilst, owing to the obliquity of the laryngeal 

 aperture, its depth rapidly diminishes ventro- 

 dorsally. Ventrally it is bounded by the dorsal 

 surface of the epiglottis, clothed with mucous Ary . epi(Tlottic 

 membrane. This wall passes obliquely from its 

 superior end in an inferior ventral direction, 

 and becomes narrower as it approaches the 

 ventral or anterior ends of the ventricular folds. 

 The superior part of the dorsal surface of the 

 epiglottis is convex, owing to the manner in 

 which the upper margin is curved ventrally 

 towards the tongue; below the convexity 

 there is a slight concavity, and still lower a 

 marked bulging or convexity, over the superior 

 part of the thyreo-epiglottic ligament. This 

 swelling is called the tuberculum epiglotticum, 

 and it forms a conspicuous object in laryngo- 

 scopic examination of the larynx. Each lateral 

 wall of the vestibule of the larynx is formed by 

 the medial surface of the corresponding ary- 

 epiglottic fold. For the most part it is smooth 

 and slightly concave, and it diminishes con- 

 siderably in vertical depth as it passes dorsally. Fm< 850 ._ FRONTAL SECTION THROUGH THE 

 In its dorsal part the mucous membrane stands LARYNX TO SHOW ITS COMPARTMENTS. 

 out in two elongated vertical elevations, placed 



one dorsal to the other (Fig. 849, p. 1068). The more ventral elevation is 

 formed by the subjacent cuneiform cartilage with the mass of glands associated 

 with it ; the more dorsal elevation is produced by the upper part of the arytsenoid 

 cartilage and the corniculate cartilage (Santorini). A shallow groove (philtrum 

 ventriculi of Merkel) passes downwards between these rounded elevations, and 

 terminates below by running into the interval between the ventricular and 

 vocal folds. The ventral elevation ends below in the dorsal extremity of the 

 ventricular fold; the arytsenoid or dorsal elevation, in its inferior part, bends 

 round the dorsal end of the ventricle of the larynx and becomes lost in the vocal 

 fold. The dorsal wall of the laryngeal vestibule is narrow, and corresponds to the 

 interval between the upper parts of the two arytsenoid 1 cartilages. Its width, to a 

 large extent, depends on the position of those cartilages, and when they .are placed 

 near each other the mucous membrane which covers the dorsal wall is thrown 

 into longitudinal folds. 



The middle compartment of the larynx is much the smallest of the three. It 

 is bounded above by the ventricular fold and below by the vocal folds, whilst it 

 communicates between those folds with the vestibule on the one hand and the 

 inferior compartment on the other. 



