AN ANALYSIS OF THE LEARNING PROCESS IN THE SNAIL 25 



TABLE IV 

 Showing the number of reactions of the mouth of two individuals of Physa gyrina 

 Say, resulting from the application of pressure alone as a stimulus, after an attempt 

 had been made to establish an association between the two stimuli, food and 

 pressure (Table III). The tests were made in filtered tap water on alternating 

 days. The snails had been starved for 24 hours preceding the tests. 



31 1 *4 3 4 



2 5 11 



3 6 11 



4 7 11 



5 8 11 



6 9 11 



7 10 

 Totals 7 8 



Av. per response 1 . 33 



32 8 1 1 1 

 9 2 11 



10-17 3-10 



Totals 10 2 



Av. per response 1.0 



33 18-27 1-10 



34 28-37 1-10 



Total number of trials (last 20 trials omitted) 17 



Total number of stimuli followed by response 8 



Per cent of stimuli followed by response 47% 



Total number of reactions 10 



Average number of reactions per trial . 58 



Average number of reactions in only those trials in which response occurred. 1 . 25 



Total time of reactions in seconds 11 



Average time per reaction in seconds 1.1 



Average number of reactions per minute (estimated) 54.54 



Snail No. 5 



No. for No. of No. of 



No. of "pressure" trial reactions Duration 



days stimulus for per of response 



tested series day response in sec. 



31 1 1 11 14 



2 2 11 



3 3 11 



4 4 12 14 



5 5 11 



6 6 5 6 



7 7 3 4 

 8-10 8-10 



Totals 10 34 



Av. per response • 4 . 85 



*For trials 1-3 on the 31st day see Table III (31st day). 



