ACCELERATOR FIBRES — CARDIAC GANGLIA AND PULSE. 



513 



was equally great after irritation of the left, as after irritation 

 of the ricjht vacuus. This shows that the accelerator-fibres in 

 the vagus are not paralysed by casca, and also that accelerator- 

 fibres, though usually, according to Boehm, contained only in 

 the riglit vagus, may occasionally be present in the left. 



Tlie effect of irritating the other accelerating nerves of the 

 heart contained in the rami cardiaci or in the sympathetic cord 

 was not examined. 



Action on Cardiac Ganglia, Effect on Pulse, &c. 

 Experiment XXXYIIL— June 10. 



A moderate-sized cat was chloroformed, and cannulce were 

 placed in the carotid artery and jugular vein. 



A solution of 3 c.c. of saturated alcoholic tincture added to 

 50 c.c. of water was used for injection into the vein. 



From this experiment it is seen that after the primary 

 slowing due to stimulation of the vagus-roots and the quicken- 

 ing due to paralysis of the vagus ends in the heart, a second 

 slowing occurs. 



This second slowing^ miojht be due either to stimulation of the 

 inhibitory apparatus in the heart or to weakening of the cardia 

 motor ganglia. 



The latter seems improbable, from the fact that each systole 

 duiing this slow period instead of being weak is exceedingly 



2 L 



