1, epiglottis; 2, portion of the thyroid cartilage (cut); 3, cricoid cartilage; 4, arytenoid cartilage; 5, trachea. a, M. arytenoideus transversus; b, M. cricoarytenoideus posterior; c, M. cricoarytenoideus lateralis; d, M. thyreoarytenoideus.
M. arytenoideus transversus ([Fig. 105], a).—A small unpaired muscle running transversely between the caudal ends of the arytenoid cartilages, just beneath the mucous membrane and parallel to the cranial border of the cricoid cartilage.
M. glossoepiglotticus.—A small longitudinal muscle, lying by the side of its fellow in the frenulum of the epiglottis.
Origin.—The median fibrous septum of the tongue.
Insertion.—The dorsal (cranial) surface of the epiglottic cartilage in the median line near its attached border.
Action.—Draws the epiglottis craniad.
M. hyoepiglotticus is a small bundle of parallel fibres lying in the frenulum of the epiglottis craniad and dorsad of the body of the hyoid bone.
Origin.—The lateral end of the cranial surface of the body of the hyoid. The two muscles pass craniodorsad, converging, and unite with the preceding.
Insertion with the preceding. (The lateral portion of the muscle may continue craniad to the tongue as a second part of the hyoglossus.)
Action.—Like the preceding.