ACTION OF THE GASTKIC JUICE UPON THE STOMACH. 277" 



him that "animals, or parts of animals, possessed of the 

 living principle, when taken into the stomach, are not in the 

 least affected by the powers of that viscus, so long as the 

 animal principle remains." 1 It was also assumed that, by 

 virtue of this principle, many animals are capable of inhab- 

 iting the stomach, living and even breeding there. It is 

 undoubtedly true that a living, highly organized part, abun- 

 dantly supplied with blood-vessels, the process of destructive 

 assimilation and nutrition taking place in its substance with 

 great activity, is protected from the action of a fluid like the 

 gastric juice by the very conditions of its existence ; but it is 

 desirable, if possible, to define these protecting conditions 

 a little more closely. It is important, moreover, to know 

 whether it is literally true that animals may maintain an 

 independent existence in the living stomach, as was sup- 

 posed by Hunter. A recent writer on this subject states that 

 there are no examples of this to be found. 2 The parasites 

 which infest the stomachs of some of the inferior animals, 

 as the horse or sheep, are firmly attached to, and, indeed, 

 partly buried in the mucous membrane. In investigating 

 the accuracy of a popular belief that lizards and various 

 other animals of that class frequently exist for a long time in 

 the human stomach, Dr. Dalton has lately shown that the 

 ordinary garden-slug and lizards, introduced living into the 

 stomach of the dog, are soon killed and are easily digested. 3 

 An interesting experiment by Bernard has shown most con- 

 clusively that the nutritive processes, as they take place in 

 cold-blooded animals, do not enable the tissues to resist the 

 action of the gastric juice. He introduced through a fistulous 

 opening into the stomach of a dog the posterior extremities 



1 HUNTER, Observations on Certain Parts of the Animal (Economy, London, 

 1792, p. 228. 



2 PAYT, On the Immunity enjoyed by the Stomach from being digested by its 

 own Secretion during Life. Philosophical Transactions, London, 1863, p. 169. 



3 DALTON, Experimental Investigations to determine whether the Garden-Slug 

 can live in the Human Stomach. American Journal of the Medical Sciences, 

 April, 1865, p. 334 et seq. 



