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depth of the lamina. It gives attachment, in front, to the middle cricothyroid 

 ligament; at the side, to the conus elasticus and the Cricoarytsenoidei laterales; 

 behind, it presents, in the middle, a shallow notch, and on either side of this is a 

 smooth, oval, convex surface, directed upward and lateralward, for articulation 

 with the base of an arytenoid cartilage. 



The inner surface of the cricoid cartilage is smooth, and lined by mucous 

 membrane. 



The Arytenoid Cartilages (cartilagines arytcenoidece) are two in number, and sit- 

 uated at the upper border of the lamina of the cricoid cartilage, at the back of 

 the larynx. Each is pyramidal in form, and has three surfaces, a base, and an 

 apex. 



The posterior surface is a triangular, smooth, concave, and gives attachment 

 to the Aryteenoidei obliquus and transversus. 



The antero-lateral surface is somewhat convex and rough. On it, near the apex 

 of the cartilage, is a rounded elevation (colliculus) from which a ridge (crista arcuata) 

 curves at first backward and then downward and forward to the vocal process. 

 The lower part of this crest intervenes between two depressions or fovese, an 

 upper, triangular, and a lower oblong in shape; the latter gives attachment to the 

 Vocalis muscle. 



The medial surface is narrow, smooth, and flattened, covered by mucous mem- 

 brane, and forms the lateral boundary of the intercartilaginous part of the rima 

 glottidis. 



The base of each cartilage is broad, and on it is a concave smooth surface, 

 for articulation with the cricoid cartilage. Its lateral angle is short, rounded, 

 and prominent; it projects backward and lateralward, and is termed the muscular 

 process; it gives insertion to the Cricoarytsenoideus posterior behind, and to the 

 Cricoarytsenoideus lateralis in front. Its anterior angle, also prominent, but more 

 pointed, projects horizontally forward; it gives attachment to the vocal ligament, 

 and is called the vocal process. 



The apex of each cartilage is pointed, curved backward and medialward, and 

 surmounted by a small conical, cartilaginous nodule, the corniculate cartilage. 



The Corniculate Cartilages (cartilagines corniculate; cartilages of Santorini} are 

 two small conical nodules, consisting of yellow elastic cartilage, which articulate 

 with the summits of the arytenoid cartilages and serve to prolong them backward 

 and medialward. They are situated in the posterior parts of the aryepiglottic 

 folds of mucous membrane, and are sometimes fused with the arytenoid cartilages. 



The Cuneiform Cartilages (cartilagines cuneiformes; cartilages of Wrisberg) are two 

 small, elongated pieces of yellow elastic cartilage, placed one on either side, in the 

 aryepiglottic fold, where they give rise to small whitish elevations on the surface 

 of the mucous membrane, just in front of the arytenoid cartilages. 



The Epiglottis (cartilago epiglottica) is a thin lamella of fibrocartilage of a yel- 

 lowish color, shaped like a leaf, and projecting obliquely upward behind the root 

 of the tongue, in front of the entrance to the larynx. The free extremity is broad 

 and rounded; the attached part or stem is long, narrow, and connected by the 

 thyroepiglottic ligament to the angle formed by the two laminae of the thyroid 

 cartilage, a short distance below the superior thyroid notch. The lower part of 

 its anterior surface is connected to the upper border of the body of the hyoid 

 bone by an elastic ligamentous band, the hyoepiglottic ligament. 



The anterior or lingual surface is curved forward, and covered on its upper, free 

 part by mucous membrane which is reflected on to the sides and root of the tongue, 

 forming a median and two lateral glossoepiglottic folds ; the lateral folds are partly 

 attached to the wall of the pharynx. The depressions between the epiglottis and 

 the root of the tongue, on either side of the median fold, are named the valleculse. 

 The lower part of the anterior surface lies behind the hyoid bone, the hyothyroid 



