236 THE RESPIRATORY APPARATUS 



inferior cornua of the thyroid cartilage. The lower 

 border is joined to the upper ring of the trachea; the 

 upper border gives attachment in front and laterally 

 to the cricothyroid membrane and the lateral crico- 

 arytenoideus muscle. Behind, at each end of its upper 

 border, is an oval surface for the corresponding ary- 

 tenoid cartilage, with a notch between. The inner 

 surface is smooth and lined with mucous membrane. 



The arytenoid cartilages are pyramidal in form, 

 presenting three surfaces, an apex, and base, and 

 rest by their bases on the highest part of the upper 

 border of the cricoid cartilage behind, their curved 

 apices approximating. 



The cornicula laryngis (cartilages of Santorini) are two 

 small, cervical nodules of yellow elastic tissue, which 

 articulate with the summits of the arytenoid cartilages 

 and serve to prolong them backward and inward. 



The- cuneiform cartilages (Wrisberg's) are two small, 

 yellow bodies of elastic cartilage, which stretch between 

 the arytenoid cartilage and the epiglottis. 



The epiglottis is a fibrocartilaginous lamella, shaped 

 like a leaf, lying behind the tongue and in front of 

 the upper orifice of the larynx. Above it is broad, 

 below narrow and prolonged to the notch above the 

 pomum Adami by the thyro-epiglottic ligament, or 

 rather, to the angular interval just below the notch, 

 and is attached to the upper border of the body of the 

 hyoid bone by the hyo-epiglottic ligament. It falls 

 downward over the opening of the larynx during the 

 swallowing of food to prevent the same from entering 

 the larynx. 



The ligaments of the larynx are extrinsic and intrinsic. 

 The former connect it to the hyoid bone; the latter 

 connect its parts together. 



The extrinsic ligaments, meaning those coming 

 from without or on the outside of the larynx, are the 

 middle thyrohyoid ligament, the two lateral thyro- 

 hyoid ligaments, and the hyo-epiglottic ligament. 



