THE SALIVARY GLANDS THE PHARYNX 



427 



THE SALIVARY GLANDS 



The parotid gland is small. Its upper part is wide and is divided into twc 

 lobes by a deep notch into which the base of the ear is received. The lower end 

 is small and overlaps the submaxillary glantl. The duct leaves the gland at its 

 anterior border, crosses the masseter muscle, and opens into the mouth opposite 

 the third upper cheek tooth. Small accessory glands (Glandulse parotidae acces- 

 sorise) are sometimes found along the course of the duct. 



The submaxillary gland is usually larger than the parotid. In large dogs it 

 is about two inches (ca. 5 cm.) long and an inch or more (ca. 3 cm.) wide. It is 

 rounded in outline and of a pale yellow color. Its upper part is covered by the 

 parotid, but it is otherwise superficial, and is palpable in the angle of junction of 

 the jugular and external maxillary veins. The duct leaves the deep face of the 

 gland, passes along the surface of the digastricus and stylo-glossus, and opens into 

 the mouth near the frenum lingutB on a very indistinct papilla. 



The sublingual gland is divided into two parts. The posterior part (Glandula 

 sublingualis grandicanalaris) lies on the digastricus muscle in intimate relation with 



Fig. 330. — Sagitt.'^l Section op PharyngeaIj and i^aryngeal Regions of Dog. 

 1, CEsophagu.s; 2, larynx; 3, mouth cavity; 4, epiglotti.s; 5, arytenoid cartilage; 6, soft palate; 6", position 

 of soft palate when raised; 7, vomer; S, base of cranium; 9, root of tongue; a, a', a" , pharynx; h, fornix of 

 pharynx; c, posterior wall of pharynx; d, floor of pharynx; e, pharyngeal surface of soft palate; /, origin of 

 oesophagus; g, vestibule of larynx; h, isthmus faucium; i. Eustachian opening; A", posterior naris. (After EUen- 

 berger, in LeL-sering's Atlas.) 



the submaxillary gland, but clearly separable from it after removal of the common 

 fibrous capsule. It has a pointed anterior process. The duct (Ductus sublingualis 

 major) accompanies the submaxillary duct, and usually opens beside it, but in 

 some cases joins it. The anterior part (Glandula sublingualis parvicanalaris) is 

 long and narrow; it lies on the stylo-glossus muscle. It has a number (8 to 12) 

 of small ducts (Ductus sublinguals minores), some of which open directly into the 

 mouth, while others join the large duct. 



The orbital or zygomatic gland (Glandula zygomatica) represents the superior 

 molar glands of herbivora. It is prismatic and is situated in the orbital region, 

 between the zygomatic arch and the internal pterygoid muscle, in contact with the 

 periorbita. It has four or five ducts (Ductus zygomatici) which open near the 

 last upper cheek tooth; one of them (canal of Nuck) is almost as large as the 

 parotid duct; the others are small. 



THE PHARYNX 

 The fornix is narrow. The orifices of the Eustachian tubes are small and slit- 

 like; the end of the tube causes a rounded projection of the mucous membrane 



