132 THE VENOMS OF CERTAIN TH AN A T P HID EiE. 



The results of the experiments with venom peptone are therefore in accord with 

 those with the pure venom and the venom globulins. 



Summary. — From the results of the observations with pure venoms and their 

 globulins and peptones upon the respiration it seems clear that the primary action 

 of all of the above poisons, excepting the copper-venom-globulin, is to cause an 

 increase in the number of respirations, and secondarily to diminish the respirations 

 below the normal. Of the different principles the peptone seems to exert the most 

 decided power in causing the acceleration, while the copper-venom-globulin seems 

 to utterly lack this action. 



Since the primary increase of the respirations does not occur in any case after 

 section of the pneumogastric nerves, this effect must be exerted by an action of the 

 poisons upon the peripheries of these nerves, and since after section of these nerves 

 a diminution of the respirations always occurs this effect must be due to a depres- 

 sion of the respiratory centres, as we have found that the motor nerves and muscles 

 of respiration are irritable long after the cessation of this function. 



