1 1 2 LABOR A TOR Y GUIDE IN PHYSIO LOG Y. 



b. The stimulation of the vagus. (Observations by 

 Group " <:.") 



(6) Stimulate moderately one vagus. Note with a 

 stethoscope whether the rate of the heart is in- 

 creased. 



(7) Cut both vagi high up in the neck. Note the 

 rate of heart beat at intervals of five minutes for 

 twenty minutes, allowing the rabbit to partially 

 recover from the anaesthesia. 



(8) Stimulate one vagus. Compare the result with 

 that obtained under experiment (6). 



(9) Will very strong stimulation bring the heart to a 

 standstill ? 



(10) If the heart was brought to a complete stand- 

 still by the stimulation, will it start up again spon- 

 taneously when the stimulus is removed? Will the 

 rate reach the degree of acceleration observed in 

 experiment (*?)? 



(11) Sum up the observations into a concise state- 

 ment as to the influence of the vagus upon the 

 heart. 



NOTE: Dispatch the rabbit with chloroform. 



