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XITI. "Experiments and Observations on the Structure and 

 Function of the Stomach in the Vertebrate Class." By 

 WILLIAM BRINTON, M.D., Lecturer on Physiology at St. 

 Thomas's Hospital. Communicated by JOHN SIMON, Esq. 

 Received June 12, 1861. 



(Abstract.) 



This paper, itself a summary of a long series of observations, may 

 be briefly abstracted as follows : 



The peculiar dimorphous structure possessed by the tubes of the 

 cardiac and middle parts of the stomach in the Dog, exists in the 

 whole Vertebrate class ; about sixty species of which are cited by the 

 author from his notes. 



Many of the variations of the stomach throughout the Vertebrate 

 class are essentially cesophageal developments, having a mechanical 

 office. 



The more essential contrasts of the vertebrate stomach refer to the 

 above dimorphous structure ; which diminishing, even in Man, to less 

 than twice its thickness in passing from the cardia to the pylorus, 

 is in most animals altogether deficient here, either with or without 

 a great shortening of the columnar-celled tubes. 



The dimorphous cell-growth is always the source and exponent of 

 the pepsinous or digestive power of the stomach on protein-com- 

 pounds ; which power is absent where this structure is deficient, and 

 present (as tested by careful comparison) in the degree in which the 

 mucous membrane contains the dimorphous cell-growth. 



Of those alternatives respecting the gastric juice suggested by va- 

 rious experiments namely (1) the secretion of pepsine by the di- 

 morphous cell-growth, and acid by the columnar ; or (2) the per- 

 fecting of the secretion (itself perhaps owing these two constituents 

 to its two kinds of cell respectively) in the open ends only of these 

 tubes the latter is, on the whole, preferable. 



The protection of the stomach from its own secretion is effected 

 mainly by the salivary and other secretions which enter it from the 

 oesophagus and duodenum. 



The living stomach decomposes a neutral or alkaline blood so as 

 to set free an acid ; but though transfused blood undergoes this de- 



