282 KANSAS UNIVERSITY SCIENCE BULLETIN. 



learn whether increasing doses of alcohol slowed or quickened 

 the reaction time; also the duration of the effect and whether 

 it varied with different intervals of time. The doses varied 

 from .05 cc. of 15 per cent per 10-gram frog up to 0.6 cc. of 

 50 per cent, and even fatal doses of 1 cc. of 95 per cent alcohol 

 per 10-gram frog were given. 



The reflex time so secured was compared with the reaction 

 time secured before alcohol was given, and in a few cases with 

 those secured after injecting Ringer solution in amounts usu- 

 ally given in alcohol. Tests were also made to see if the 

 mechanical stimulus of the needle would be a disturbing factor. 

 From these observations the influence of alcohol upon the re- 

 flex centers of some of the different cutaneous sensory spots 

 was deduced. 



It was demonstrated that each spot had its own reflex time 

 and its own degree of irritability, and that some were more 

 resistant to the influence of alcohol than others. Spot c, 

 figure 1, for instance, was especially resistant; the acid paper 

 rubbed off within one second, and weak doses of alcohol that 

 affected the reflex time of all the other spots produced no 

 effect upon this spot. Not until a dose of 0.3 cc. of 30 per cent 

 alcohol per 10-gram frog was given did the spot fail to re- 

 spond, and then only for a short time. Larger doses, 0.6 cc. 

 of 50 per cent alcohol per 10-gram frog, that caused a loss of 

 the reflexes of the other spots and a depression of the turn- 

 over and other higher reflexes, would, however, cause a loss 

 of response from this spot as well. 



It was shown that alcohol in quantities so small that it ap- 

 parently produced no effect whatever upon the frog has a de- 

 cided influence upon the reflex centers of some of the cutaneous 

 areas ; at least in .so far as to lower their irritability and to 

 prolong their reaction time. When once affected by alcohol, 

 they do not become normal in their response again for some 

 time. 



From repeated tests in a large series of experiments it was 

 seen that doses less than 0.05 cc. of 15 per cent alcohol per 10- 

 gram frog had no more effect upon the reflex time than had an 

 equal amount of Ringer solution. But beginning with 0.1 cc. 

 of 15 per cent alcohol, all the other doses that were given had a 

 depressing effect upon the reflex actions; that is, they caused 

 the interval between stimulations and response to be prolonged 



