THE GASTRIC MUCOSA 201 



their text-book of Histology showing typical mucoid cells — 

 svhich they hesitatingly label ' cellules principales muqueuses ? ' 

 — to illustrate the mucus cells of Bensley. It is evident, 

 therefrom, that hitherto the distribution and even the existence 

 of mucoid cells have scarcely been recognized. 



The names ' peptic ' and ' mucoid ' have been chosen for 

 obvious reasons. The structure of the peptic cell is charac- 

 teristically that of a zymogen-secreting cell, and by the term 

 ' chief ' or ' central ' this cell was meant, so that there is no 

 need to dispute its function. The term mucoid is applied 

 because the cell resembles other mucus-secreting cells, but it 

 is not identical either with the mucus-secreting cells lining 

 the surface or with the goblet cells of the intestine (compare 

 cells m and s in PI. 8, fig. 8 ; also see Lim (17)). 



We may next consider the relation between the cardiac, 

 pyloric, and mucoid cells. We have seen that there is little 

 or no difference structurally between the two former (cardiac 

 and pyloric) cells, and that the mucoid cells resemble them in 

 most respects except position. They are stained in the same 

 way, and their structural characters are very similar both 

 during rest and activity. The cardiac and pyloric cells show 

 in some animals a reddish basal reticulum ; this may or may 

 not constitute a difference, although it is to be noted that the 

 reticulum is more frequently absent than present. Lastly, 

 they are continuous with each other, for cardiac cells can be 

 traced into the fundus in the form of mucoid cells : the same 

 applies to pyloric cells. The close resemblance which thus 

 exists ])etween these three types (they are all ol)viously mucoid) 

 presumes a similarity in their functions. 



The striking differences in structure between the peptic 

 and pyloric cells have been quite missed by all the workers 

 on pyloric pouches, and it is possible that their histological 

 examination was inadequate to ensure the purity of the 

 pouches which they made. But apart from this the suggestion 

 that pepsin is secreted by cells which are not typical of the 

 zymogen-secreting type calls for a closer investigation into 

 the origin of the secretion of the pyloric pouches. 



