39 

 ■before the rapid descent in the curves is made. After 



this the curves are more regular. 



Besides this general appearance of the curves ,therw 

 are some individual differences in the curves of the latch- 

 box t maze and inclined plane "box which are worthy of notice, 

 The most irregular ones are those of the inclined plane 

 "box and the maze. This is also true of the individual 

 curves representing one, three and five daily trials. 

 This irregularity is again more pronounced in the early 

 trials and is an indication that the problems are more 

 difficult than that of the latch-box. The inclined plane 

 box i§ the most complex and this condition is probably 

 due to the neural associations which must be formed. 

 Additional indication of this is seen in the number of 

 trials required before the drop in the curves takes place. 

 More such trials are necessary an the problems of the 

 maze and inclined plane box than of the latch-box. This 

 and the additional fact that learning is increasingly 



