SECRETION PHYSIOLOGY. 343 



2. If the gland be left without stimulation for a minute after 

 decapitation the total amount of saliva obtainable is considerably 

 reduced. 



3. If the gland be not stimulated until 3 or 4 minutes have 

 passed a small secretion may be obtained 6 minutes after decapi- 

 tation. (Experiment XVIII.) 



4. If air be blown into the carotid artery, after cutting off 

 the head, the secretion of saliva is reduced in amount and se- 

 cretion ceases, either abruptly or after 2 to 3 minutes. (Experi- 

 ments LXIII, LXVI and LXVII.) 



5. If defibrinated blood be run under small pressure into the 

 vein of the gland a small secretion may be obtained 20 to 30 

 minutes after clamping the gland artery. 



6. If the blood supply be cut off for 30 minutes, on read- 

 mitting blood the arterioles dilate, arterial colored blood issues 

 from the vein at a rapid rate and a spontaneous secretion begins. 

 The rate of this secretion is not changed by stimulation of the 

 chorda in the first minute. (Experiment Va.) 



Experiment Va. 



Large dog. 3 cc. i % morphine sulph. subcut. Tracheot- 

 omy. Ether. Canulae in both submaxillary ducts. Both 

 chordo-linguals and both sympathetics cut. The left vagus sub- 

 sequently divided also. The right gland is stimulated from 

 time to time. See p. 305. The left is freed from its tunic and 

 is attached only by the hilum. The vein on the upper surface is 

 open and flows continuously. The only blood vessel coming 

 to the gland is the hilum artery. The other artery was tied and 

 cut. 



Readings computed in cc. 







Time. 



Nerve. Amount of Secretiom 



h 



m 



s h m 



s 



^ 







25 





Clamped artery going to gland. 



3 



25 



- 3 30 



c Gradually less. 



3 



30 





c None. 



3 



32 





c '* 











35 





s .07 



