14 



JOHN LINCK ULRICH 



It will be seen that the first rat completed learning with one 

 trial every third day in 9 trials, with one trial every other day 

 also in 9 trials, and with one trial every day in 11 trials. The last 

 rats to finish in these experiments did so in 17, 22, and 24 trials 

 respectively. On the whole fewer trials are necessary to learn 

 a problem when trials or periods of learning are distributed 

 over several days. 



The curves, Curve II, below representing the progress of 

 integration must still be described. They were plotted from the 



CURVE 



LATCH BOX 



ONE TRIAL CVCBY.DAY 



ONE TRIAL EVERY OTHER DAY 



ONE TRIAL EVERY TWO DAYS 



averages of Table II. The individual curve of the one trial 

 group is plotted again to show the difference between it and the 

 curves representing the groups working every other day and 

 every third day. These latter curves have the same general 

 appearance and contour as the former (1 trial), though they 

 show some essential differences. The curve for one trial daily 

 is the longest and the most irregular, especially the part indi- 

 cating the early trials in learning. The shortest and most regular 

 is the one plotted for a trial every third day. In addition, this 

 particular curve shows that relatively few trials were required 



