266 



AMYLOLYTIC POWER AND CHEMICAL 



in the solid matter secreted. At 10.40 p. M. amylolytic power 

 shows a still greater fall, although alkalinity and solid matter 

 are increased in amount. 



How far are the preceding variations in the secreted saliva 

 due to the combined influence of taking food and the mechani- 

 cal stimulation incidental to mastication of the rubber, and 

 how far to a natural variation in the composition of the 

 secretion? This question we have endeavored to answer by 

 noting the variations in the saliva on a day when food was 

 abstained from, and by collecting the saliva without move- 

 ment of the jaws. This was accomplished by simply resting 

 the head on the hands, with the mouth downwards, and 

 allowing the saliva to drip into a beaker without any unneces- 

 sary movement.* In this way 15-20 c. c. of saliva were 

 collected in half an hour. 



Following are the results obtained : 



A study of these results shows clearly that when the stimu- 

 lating influences of food and mastication are withdrawn, con- 

 spicuous alterations in the composition and physiological action 

 of the saliva are still found, as though there might be a normal 



See Hofbauer, loc. cit, p. 508. 



t This result is of somewhat questionable accuracy, having been obtained 

 with a very small amount of saliva. 



