28 



THE (ESOPHAGUS. 



It is the strongest of all the 

 Fig. 134* 



cellular (cellular or nervous coat,) forms a perfect cylinder, 

 and is composed of fibres of condensed cellular tissue inter 

 crossed in different directions, 

 tunics, and gives to the canal 

 its greatest power of resisting 

 internal distension. The nerves 

 ramify abundantly in this tunic 

 before they reach the mucous 

 coat ; hence the organic sufFer- 

 hicr and often sudden death, 

 resulting from sudden tympani- 

 tic distension of the alimentary 

 canal. The mucous membrane 

 of the canal is every where 

 continuous. It is of a reddish 

 color, soft and spongy in its 

 consistence, and varies in its 

 thickness, and in the number 

 of the villi, follicles, and folds, 

 which it forms in different portions of the canal. — 



Of the (Esophagus. 



The OEsophagus is a muscular tube which passes from the 

 pharynx to the stomach, and is so intimately connected with 

 the stomach, that it will be advantageous to the student to 

 attend to its structure immediately before he engages in the 

 examination of that important organ. 



* Fig. 134. The pharynx slit open behind, in order to show the relative 

 position of the opening of the posterior nares, the velum pendulum palati, the 

 floor of the mouth, and the opening of the larynx, a, Base of the cranium. 

 b, Mastoid process of the temporal bone, c, Vertical partition between the 

 nasal fossce, and upon each side of it, the posterior opening of the nares. d, 

 Velum pendulum palati, a fleshy appendage to the osseous palate; at its middle 

 part, projecting downwnrds and backwards is seen the uvula, and on each side 

 of the uvula, are seen the buccal cavities, e, Base of the tongue. /, Extrem- 

 it)'' of the OS hyoides ; on the opposite side, this bone is entirely concealed by 

 the portion of the posterior wall of the pharynx, which is folded outwards, g, 

 Glottis, or opening of the larynx ; the epiglottis is seen above and in front of 

 this opening, and is in this figure applied against the base of the tongue. A, 

 Part of the trachea, i, Commencement of the oesophagus. I; Levator pharyn- 

 geus muscle. — 



