374 STELLA B. VINCENT 



made first, made most frequently and therefore persist longer. 

 On the other hand, it may be that the food box as the final 

 and probably the strongest member of the motor series may 

 become more directive and react back into and help to organize 

 the later members of the series most closely connected with it 

 in time much as other memory series — not motor — are known 

 to be organized. 



The black-white maze influenced the distribution of errors 

 but as the rat's vision is notoriously poor the influence was 

 chiefly seen in the smaller amount of difference between the 

 records of the first and the last cut de sacs as the character of 

 the distribution remained the same. 



In the open maze the errors were more evenly distributed 

 for the reasons given above. The animals in the olfactory maze 

 were really learning to follow a trail and incidentally learning a 

 motor series. The incidental errors increased toward the end 

 of the series although the last two counts show a balance in 

 favor of 5, 6 and 7. The experiment when the trail was in the 

 cul de sacs gave a situation where the true path resembled that 

 of the normal maze but the cul de sacs were made more attrac- 

 tive because of the odor and thus influenced the totals. The 

 last three counts, however, are lower for 5, 6 and 7 in this 

 experiment also. 



Sensory clues in these mazes, not only favor accuracy but 

 also affect the distribution of the errors among the members 

 of the series of blind alleys. The influence is seen both in the 

 degree of difference and in the character of the distribution. 

 The distribution could be said to be less mechanical and not 

 quite so predictable as in the normal maze although on the 

 whole the relations were similar in all of the mazes. 4 The final 

 members of the cul de sacs were entered less frequently and elimin- 

 ated first. 



4 Since making these tabulations and comparisons Miss Hubbert's paper has 

 appeared, " Elimination of errors in the maze," Jour. Animal Behav., Vol. 5, No. 1. 

 Her results contradict those reported here, but this work must stand on its own 

 merits. I cannot at this place enter into a discussion of Miss H's. paper. It 

 scarcely seems fair, however, when there are so few cul de sacs, to eliminate the 

 first and the last, where the chief differences are seen, from the comparison. There 

 is always overlapping in the middle of any series. If the nature of the maze com- 

 pelled this elimination then no general conclusions should be drawn. 



