MAZE STUDIES WITH THE WHITE RAT 275 



siderable disturbance was manifest when the maze was uncovered. 

 This difference in results is more comprehensible when the situa- 

 tion is stated in the following terms: — The removal of stimuli 

 (change from a heterogeneous to a uniform environment) is 

 without effect, while the introduction of novel stimuli operates 

 as a disturbance. This conception would indicate that the rats 

 after mastering the maze do not rely to any great extent upon 

 the objective stimuli as guides or controls in traversing the 

 maze, and that the introduction of unfamiliar conditions operates 

 as a distraction. 



This paper makes no pretense of defining in physical terms 

 the nature of the environmental alterations. Rotation of the 

 maze may disturb the normal relation of the animal to the 

 optical, olfactory, or auditory aspects of the environment. 

 Likewise we make no pretense of knowing through what sense 

 avenue these disturbances were mediated. We were interested 

 primarily in establishing the fact that the rats are sensitive 

 to these alterations in some way and that stability of sensory 

 conditions is conducive to the development of an automatic 

 act. 



