1134 



DIGESTIVE SYSTEM 



best developed in childhood. After the age of puberty, they usually undergo certain retro- 

 gressive changes, become smaller in size, and in old age become almost entirely atrophied and 

 lost. They are also markedly subject to inflammatory hypertrophy, especially in children. 

 Variations in the relations of the blood-vessels were mentioned above. 



The laryngeal pharynx (fig. 848) is the lower portion leading from the oral 

 pharynx above into the oesophagus below (at the level of the lower border of the 

 cricoid cartilage, usuall}- opposite the sixth cervical centrum). It is wide above 



Fig. 892. — The Muscles of the Soft Palate and the Palatal Arches as Seen from in 

 Front. (After Toldt, "Atlas of Human Anatomy," Rebman, London and New York.) 



Incisive papilla 



Transverse palatine ridges 

 Angle of mouth 



Hard palate 



Second molar 



Mucous membrane — i 

 of cheek 



Maxillary tuberosity — ^ 



Hamulus of internal ' 

 pterygoid plate 



Tendon of tensor veh 

 palatini 



Periosteum 



Levator veli palatini 



Pharyngo-palatine arch 



Uvula *" 



Palatine tonsil 



Glosso-palatine ai ch 



Mucous membrane of floor ~~ 

 of mouth 



Soft parts of cheek (cut) 



Oral vestibule 

 Palatine glands 



Palatine foramen with 

 anterior palatine nerve 



-Posterior nasal spine 



'^~" Buccinator 



Pterygo-mandibular raphe 



Levator veli palatini 



Constrictor pharyngis 

 superior 



"*-=^ Pharyngo-palatinus 

 /' 



Glosso-palatinus 

 '*— Eucco-pharyngeal fascia 

 Palatine tonsil 



//W Stylo-glossus 



Isthmus of the fauces 



Dorsum of tongue 



and narrow below (fig. 888). Its poster mr walls are continuous with those of the 

 oral pharynx and in relation with the vertebral centra. Its lateral walls are 

 attached to the hyoid bone and the posterior part of the medial surface of the 

 thyreoid cartilage. Anteriorly it is in relation with the larynx. In the median 

 line above is the epiglottis, below which is the superior aperture of the larynx. 

 Still lower is the posterior wall of the larynx, containing the arytoenoid and lamina 

 of the cricoid cartilage. Laterally, are the pliaryngo-epiglottic folds, and below 

 these on each side a deep, elongated fossa, th(; 7'eccssus piriformis, bounded 

 laterally by the medial surface of tlu; thyreoid cartilage. The mucosa of the laryn- 

 geal pharynx is similar to that of tlie oral pliarynx, and contains racemose mucous 

 glands, which are especially numerous in its anterior wall. 



Muscles of the pharynx and soft palate.— These muscles (figs. 892, 893, 894), 

 which are here; grouj)ed together for convenience of description, are chiefly 

 sphincter-like constrictors in function. They include the constrictors of the 

 faucial isthmus (mm. glossopalatini), the constrictors of the pharyngeal isthmus 



