206 



PHYSIOLOGY OF ALIMENTATION 



Hours after feeding 

 2 3 



\ 



10 



\ 



\ 



A B 



FIG. 25. 



A = ordinary curve of gastric secretion. 



B= curve from direct introduction of food into stomach. 



demonstrated by comparing gastric digestion in which it is 

 allowed to play a part, with gastric digestion in which the 

 psychic element is shut out. This can be readily done in an 

 cesophagotomized dog which possesses a fistula leading into 

 the main stomach in addition to having a gastric cul-de-sa?. 

 If food is introduced into such a dog's main stomach 

 without attracting its attention, it is found that digestion 

 goes on at an entirely different rate than when the psy- 

 chic element is allowed to play a part. Under these cir- 

 cumstances, bread and coagulated white of egg do not yield 



