TEMPERATURE SENSES IN FROG S SKIN 



99 



If the receptors for heat He deeper than those for touch and 

 cold, as is true in the human skin, it seemed that it would be 

 possible to affect them sooner by a solution of cocaine and thus 

 demonstrate the independence of the two senses. This was 

 attempted by stimulating a normal and a cocained foot with the 

 falling shot and with heat. Some difficulty was experienced in 



TABLE 8 

 Responses in seconds to touch and heat. Touch stimulation shot, rolled through 

 tube striking tipon surface of the foot. Right foot cocained 10 to 20 minutes. 

 Left foot normal. Reaction alloxvance, 30 seconds. Stimulation time, 2 minutes. 

 CO = no response 



keeping the skin from being exhausted by tactile stimulation 

 before the cocaine treatment was finished. Frogs which strug- 

 gled had to be repeatedl}^ adjusted, and this could hardly be 

 accomplished without touching the frog somewhere. It was 

 necessary, therefore, to perform a good many experiments and 

 to select quiet frogs. Fifteen such frogs were used, and from their 

 records the five in table 8 were selected. In these fifteen frogs 



