THE PHARYNX — THE OESOPHAGUS 



389 



is salmon pink in color. It has a single duct (Ductus sublingualis major), which 

 either opens alongside of or joins the submaxillary duct. 



THE PHARYNX 



The pharynx is short and wide. The vault (Fornix pharyngis) is divided into 

 two cul-de-sacs l)y a median fold of mucous membrane (Septum nasi membrana- 

 ceum), which is a continuation of that of the septum nasi; on the outer wall of 

 each is the relatively small opening of the Eustachian tube, which is covered by a 



Fif!. 287. — Salivary Glands of Ox. 

 a. Parotid gland; 6, submaxillary gland; c, inferior, d, middle, and e, superior buccal glands; /, labial 

 glands; ff, buccinator nerve; A, buccinator vein; i, masseter (cut); .2, ramus of mandible; 3, zygomaticus muscle; 

 4, conical papillae of lip: 5, buccinator muscle. (After EUenberger, in Leisering's. Atlas.) 



simple fold of mucous membrane. The posterior nares are small. The entrance 

 to the oesophagus is large. 



On the dorsal wall of the pharynx are two large pharyngeal lymph glands, which, when 

 enlarged, cause difficulty in swallowing and breathing (Fig. 281). 



THE (ESOPHAGUS 

 This is much shorter, wider, and more dilatable than that of the horse. Its 

 average diameter (when moderately inflated) is about two inches (ca. 5 cm.), and 

 its length in a large animal is about three to three and a half feet (ca. 90 to 100 cm.). 

 The wall is relatively thin, and the muscular tissue is striped throughout. The 

 latter consists of two strata of spiral fibers, except near the stomach, where they 

 are longitudinal and circular. Fibers are continued into the wall of the stomach 



