THE MOUTH 



445 



large pointed conical papillae (Papillae conicse), which are directed toward the 

 isthmus faucium and are covered with a horny epithehum. The largest of these 

 have a length of about half an inch (ca. 1 to 1.5 cm.) and are situated around 

 the angle of the mouth and parallel with the cheek teeth. The orifice of the parotid 

 duct is opposite the fifth upper cheek tooth. The buccal glands (Fig. 385) are very- 

 well developed, and are arranged 

 in three parts. The dorsal part 

 extends from the angle of the 

 mouth to the maxillary tuberos- 

 ity ; its lobules are of a light yel- 

 low color. The ventral part con- 

 sists of a compact brownish mass 

 which reaches from the angle 

 of the mouth a short distance 

 under the masseter muscle. The 

 middle part consists of loosely 

 arranged yellow lobules. The 

 small ducts of these glands open 

 between the papillae of the cheek. 



A linear series of large pa- 

 pillae exists on the floor of the 

 mouth on each side of the frenum 

 linguae. Near these are found 

 the openings of the small ducts 

 of the sublingual gland. The 

 caruncula sublingualis, the pa- 

 pilla on which the sub-maxil- 

 lary duct opens, is wide, hard, 

 and has a serrated edge (Fig. 

 383). 



The hard palate is wide, and 

 is usually more or less pigmented. 

 The body of the premaxilla is 

 covered with a thick layer of 

 dense connective tissue, which 

 has a thick, horny epithelial cov- 

 ering — forming the so-called den- 

 tal plate or pad. The palatine 

 ridges extend from this back- 

 ward about two-thirds of the 

 length of the hard palate; they 

 number 15 to 19. They are 

 nearly straight, and, with the 

 exception of a few at the poste- 

 rior end of the series, are serrated on the free edge. A median raphe extends 

 between the ridges. The posterior third of the palate is smooth. Between 

 the dental plate and the first ridge is the triangular papilla incisiva; on either 

 side of this is a deep furrow, in which is the oral opening of the ductus incisivus.i 

 The duct is two inches or more (ca. 5 to 6 cm.) in length and opens on the floor 

 of the nasal cavity; it also communicates by a slit-like opening with the vomero- 

 nasal organ. 



1 This is also known as the naso-palatine canal. 



Fig. 3S0. — Habd Palate op Ox. 

 1, Dental pad or plate; 2, placed on papilla incisiva with lines 

 to orifices of ductus incisivi; 3, ridge of palate; 4, rapM of palate; 

 5, smooth part of palate showing orifices of palatine glands; 6, 

 upper lip; 7, conical papillae of cheek. 



