

A. ORAL CAVITY, BY E. KLEIN. 507 



cous membrane of the nasal passages. The mucous membrane 

 of the soft palate is continued laterally and downwards as the 

 arcus palato-glossus into that of the root of the tongue, and 

 as the arcus palato-pharyngeus into that of the pharynx. 



In newly born children the apex of the uvula and the im- 

 mediately adjoining parts are covered with tesselated epithe- 

 lium, whilst the posterior or upper surface is invested with 

 a laminated cylindrical and ciliated epithelium. The most 

 superficial cells are here beset with short hair-like processes, 

 present a conical form, with the apices directed away from the 

 surface, and contain rounded or laterally flattened nuclei; 

 subjacent to these are fusiform or elongated oval cells, and 

 still deeper lie others that are flattened at the sides by mutual 

 pressure. 



The transition of laminated pavement epithelium into lami- 

 nated cylindrical and ciliated epithelium is effected by a 

 diminution in the number of the middle layers of the cells, 

 which are not arranged as before, with their shortest diameter 

 perpendicular, but parallel to the surface; and by the dis- 

 appearance of the most superficial flattened cells, which are 

 replaced by cylinder cells, that increase in number in propor- 

 tion to their distance from the apex of the uvula. 



On the posterior surface of the uvula and of the soft palate 

 of the new-born infant there may moreover be found nume- 

 rous isolated areas, presenting well-developed pavement epi- 

 thelium, as well as transitional forms between the laminated 

 cylinder and pavement epithelium. In adults* a laminated 

 pavement epithelium exists both on the anterior and on the 

 posterior or superior surfaces of the uvula and soft palate, 

 and this may be divided into two layers, of which the cells 

 forming the deeper are smaller than those of the superficial. 



The tissue of the mucous membrane contains fasciculi 

 of connective tissue, and a considerable quantity of coiled 

 elastic fibres of various size united into plexuses. The part 

 situated immediately beneath the epithelium, is much closer 



* E. Klein, Uber das Epithel des Weichen Gaumes, etc., "On the Epi- 

 thelium of the Soft Palate," etc. ; Wiener Sitzungsberichte der k. k. Akade- 

 mie der Wissenschaft. zu Wien, Januar heft, 1868. 



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