AN ANALYSIS OF THE LEARNING PROCESS IN THE SNAIL 71 



TABLE Kl— (Continued) 

 Summary — Snail No. 11 — (Continued) 



Total number of trials 178 



Total number of correct trials 75 approximately 42% 



Total number of incorrect trials 103 approximately 58% 



Summary— Snail No. 27 



No. of 



days No. of Correct Incorrect 



tested trials choices choices 



14 2 2 



2 3 12 



3 5 1 4 



4 6 15 



5 5 14 



6 4 4 



7 4 2 2 



8 7 7 



9 5 4 1 



10 6 2 4 



11 5 3 2 



12 3 1 2 



Total number of trials 57 



Total number of correct trials 18 approximately 32% 



Total number of incorrect trials 39 approximately 68% 



TABLE XI-A 

 Summary of Rough-Shock-Smooth Tests 



Snail Snail Snail Snail 



No. No. No. No. 



9 10 11 27 



Total number of trials 215 



Per cent of incorrect choices 56 



214 

 65 



178 

 58 



57 

 68 



Table XI shows the trials of four snails on the rough-shock- 

 smooth Y-shaped labyrinth. These cover periods of 38, 35, 25, 

 and 12 days and involve 215, 214, 178, and 57 trials, or a total 

 of 664 trials. Of these 401 or 60.3% give wrong choices. The 

 curves (figs. 19-22, Plate VII) show great irregularity, especially 

 in the first third of their courses. Nearly all the days on which 

 the choices w^ere either all right or all wrong fall in this part of 

 the curves. After this the curves fluctuate less froin the fifty 

 per cent level, but rise slightly as they proceed. In this series 

 the snails climb a labyrinth of cylindrical glass and are free to 

 move on any side of it; there is no question of right or left. 

 The choice is made between rough and smooth. No rough- 

 smooth preference tests were made, 'but there is evident in this 



