82 NUTRITIONAL PHYSIOLOGY 



through the skin of the neck. Whatever is swallowed by 

 the dog is now returned to the exterior. The pleasure of 

 eating is not impaired. To maintain nutrition suitable 

 food may be introduced directly into the stomach. When 

 the dog chews and swallows a meal he is quaintly said to 

 have a "Scheinfutterung" a fictitious feeding. This 

 proceeding is accompanied by a steady flow of the secre- 

 tion from the gastric fistula. 



The secretion obtained under circumstances like the 

 above is called the psychic secretion. This term serves to 

 emphasize the fact that a mental element is a necessary 

 incident of the reaction. The conditions governing gastric 

 secretion seem to be quite parallel with those which regu- 

 late the movements of the stomach, and their importance 

 in hygiene is equally evident. There are a number of 

 individuals who have in various ways lost the power to 

 swallow food, commonly because of the closure of the 

 esophagus. Their lives are preserved by feeding through 

 gastric fistulas established by surgery. These unfortu- 

 nates find it to their advantage to attend to the idea of 

 eating, and to taste and chew portions of their food at the 

 time when it is being introduced into their stomachs. 



After a brief period of fictitious feeding the flow of 

 gastric juice into the stomach of a dog may continue for 

 two or three hours. In view of this we must conclude 

 that, however important the mental state may be for the 

 initiation of the process, it need not be its accompaniment 

 throughout. We cannot pretend that a meal receives our 

 constant attention during any such interval. Neverthe- 

 less we are hardly likely to overestimate the necessity of 

 securing a normal start. If the initial circumstances are 

 not favorable the secretion may be long delayed or even 

 lacking. 



Now that we have reserved a due place for the psychic 

 element, we must pass on to consider the other factors 

 which modify the activity of the glands of the stomach. 

 Much has been learned from the surprising operations of 

 Pawlow and others, who have succeeded in dividing the 



