THE GASTRIC MUCOSA 205 



cells become mucoid in character throughout the whole 

 stomach. The next type to differentiate is the oxyntic, and 

 at a later stage still comes the peptic. 



Peptic cells are present in the human foetus at birth, but 

 in the cat do not appear until between the second and third 

 week after l)irth. 'I'his difference may give an important 

 clue to the function of the fundic mucoid cells, for it has been 

 observed that the new-born human stomach contains pepsin 

 while the stomach of the new-born cat contains none, and does 

 not exhibit a ferment until the third week after birth ((Ham- 

 marsten 1874, Zweifel 1874, Morrigia 1876) quoted by Moore 

 (2), Sewall (3)). Obviously pepsin is not secreted by the mucoid 

 cells. 



These cells are essentially primitive, or at least less specialized 

 than either the peptic or oxyntic. Cade arrives at a parallel 

 conclusion from an entirely different point of view (1). He 

 found that oxyntic cells disappear and peptic cells lose their 

 granules in the vicinity of gastero-enterostomy openings, and 

 all the cells appear mucoid in character. He thus inferred that 

 the altered conditions had caused the specialized cells to revert 

 to the more primitive mucoid cells. In cats I have been able 

 to confirm Cade's observation completely. 



Thus while the mucoid cells are undoubtedly a definite variety 

 of the gastric gland-cells they are closely allied to the peptic 

 cells to which they give rise in early and perhaps in later life. 



Literature. 



1. Cade.—' Arch, d'anat. niicr.', 1901, iv. 1. 



2. Moore.—' Schafer's Text-book of Physiology ', 1898, i. 330. 



3. -Sewall.—' Journ. Physiol.', 1878, i. 321. 



PART in. THE GASTRIC MUCOID CELLS IN MAN, 

 DOG, RABBIT, AND FROG. 



The gastric mucous membrane of several species of animal 

 has been examined in order to compare the histological features 

 and the distribution of the mucoid-reacting cells in each 



P 2 



