248 ZOOTOMY. 



about a quarter of an inch long, with its backwardly directed 

 apex passing into a duct which opens in a distinct median 

 papilla. 



XLVIII. Cut through one side of the lower jaw 

 near its articulation, open the mouth widely, and 

 observe : 



297. The palate, or roof of the mouth, marked by a 

 median longitudinal slit, bounded by two fimbriated folds 

 of mucous membrane, between which are the posterior 

 nares. 



298. At the posterior end of the palatal folds is the 

 single median aperture of the Eustachian tubes, 

 which communicates, right and left, with the tympanic 

 cavities ( 318), 



299. The velum palati, a bilobed flap of mucous 

 membrane, with fimbriated edges, forming the posterior 

 termination of the palate. 



300. The tongue, pointed in front, bifid and fimbriated 

 behind. 



301. The glottis, an oval aperture just behind the root 

 of the tongue, leading into the trachea : its margins are 

 slightly fimbriated, and immediately behind it is a bilobed 

 fimbriated fold of mucous membrane. 



302. The wide pharynx, leading into the gullet. 



303. By dissecting away the mucous membrane of the 

 glottis, the larynx is found, a cartilaginous apparatus form- 

 ing the anterior end of the trachea. 



The larynx consists of the following parts : (a) the thyroid, a 

 partly ossified cartilaginous plate, bent upon itself in the form of a 

 dorsally incomplete ring, wide and scoop-shaped ventrally, narrow 

 dorsally : (b) the cricoid, a small longitudinal rod of cartilage, inter- 

 posed between the dorsal ends of the thyroid : (c) the arytenoids, 

 paired, somewhat triangular cartilages, ossified at their proximal ends, 

 where they articulate with facets on the anterior end of the cricoid ; 



