REDINTEGRATION IN ALBINO RAT— A STUDY IN RETENTION 39 



may or may not have exhibited perfect integration, yet 

 it was necessary for each individual to have exhibited 

 perfect integration of movement in at least the first six 

 trials of the norm. From these facts it is evident that 

 although at the end of the fifteen trials of the norm it is 

 possible that no two individuals began retention with the 

 necessary integrations established in the same degree of 

 precision, yet all acquired the habit, as was shown in the 

 first six perfect trials of the norm, and all underwent 

 experiment according to the same standard. 



Experiments with the present group of rats were under- 

 taken in the attempt to ascertain some influence of in- 

 complete learning on redintegration after retention. Two 

 litters composed of five rats each were chosen for the 

 present work and set to learn the maze by the one trial 

 per day method. The standard norm and methods were 

 applied to both litters, except that when the norm of fifteen 

 trials had been completed by the first rat of each litter 

 the whole litter was put on retention regardless of how 

 far the learning had progressed with the remaining four 

 rats. The same method was employed in redintegration. 



Tables VII-A and VII-B contain the records of these 

 two litters in " errors," trials, and time. In Table VII-B 

 it may be seen that, in litter 1, rat 5 was the first to com- 

 plete learning, in S3 trials; but in redintegration, rat 2 

 was the first to finish, in 15 trials. In litter 2, rat 9 was 

 the first to finish learning, in 25 trials; but in redintegra- 

 tion, rat 10 was the first to finish, in 15 trials. At first 

 sight it may appear somewhat questionable that in both 

 cases cited the individual which finished first in learning 

 according to the norm did not finish first in redintegration. 

 But this fact simply points out that the rat which learned 

 the problem first according to the norm seems not to have 

 been the one which had most firmly established integra- 

 tion during learning, and hence was not the best in redin- 

 tegration. The apparent discrepancy in the redintegration 

 records must be solved, at least in part, from the records 

 of the learning. 



Considering first the learning of litter 1, in Table VII-B 

 (supplement), it may be seen, first, that three rats of the 



