68 ILLINOIS BIOLOGICAL MONOGRAPHS [188 



7. A fifth method of pharmacodynamic testing has been suggested which 

 consists of comparing the velocity of fatality curve of an unknown solution 

 with that of a known solution of the same substance. The strengths of the 

 solutions are inversely proportional to the number of cc. per 1. of the original 

 solutions or the number of grams per 1. of the two substances required to make 

 up a theoretical threshold of toxicity concentration of the substance. 



8. A rise in temperature increases the toxic activity of a substance which 

 probably follows the same general law as that of the activity of toxic substances. 

 This has not been proven and needs further investigation. 



