CHAP, vii.] SPECIAL MUSCULAB, MECHANISMS. 1071 



L 



FIG. 183. DIAGRAM OF A LARYNGOSCOPIC VIEW OF THE LARYNX (magnified 



twice). 



L. the base of the tongue, e. the epiglottis, seen foreshortened with ' its 

 cushion, ar.ep.f. the ary-epiglottic folds. W. the Capitulum Wrisbergi, 8. Cap- 

 itulum Santorini ; the mucous membrane between the arytenoids is stretched 

 straight, the notch being merely indicated, c.v. vocal cords, c.v.s. ventricular 

 bands, v.l. the opening into the ventricle of the larynx seen between them. The 

 former, bounding the widely open glottis of more or less triangular form, through 

 which a view of the trachea (ZY.) is obtained are seen to end in the processus 

 vocales (p.u.). 



On each side of the larynx is seen s.p. the pyriform recess, ph. the hind wall 

 of the phlarynx. l.f. the median glosso-epiglottic fold. 



of Santorini a shallower prominence due to the top of the aryte- 

 noid itself, shewn at a in Fig. 187 B. Between the two phases 

 of complete apposition and of the widest separation of the tuber- 

 cles of Santorini, intermediate phases may from time to time be 

 seen, such as those shewn in Fig. 183, Fig. 187 B. 



These several structures define the superior aperture of the 

 larynx which in the laryngoscopic view, owing to the foreshort- 

 ening, is not seen as it is in a dissection (Figs. 184, 185, 186) 

 namely as a slanting orifice with a long fore and aft diameter 

 but appears as a rhomboidal space with the transverse diameter 

 generally the longer one. If no voice is being uttered, and the 

 breathing be gentle and quiet, the glottis may be seen within 

 this aperture as a slit, more or less in the form of an elongated 

 isosceles triangle with the apex dipping beneath the cushion of 

 the epiglottis, the sides formed by the vocal cords, and the base 

 by the arytenoids with the membrane between them. In a favour- 

 able view (Fig. 183) the vocal cords (v.c.) may be seen to be 

 attached to the processus vocales and the distinction between 

 the membranous and cartilaginous glottis observed. On the 

 outside of each vocal cord, separated from it by the mouth of 



