CHAPTER XI 

 THE ROLE OF SIGHT IN THE DAILY LIFE OF THE DANCER 



DARTING hither and thither in its cage, whirling rapidly, 

 now to the left, now to the right, running in circles, passing 

 through holes in the nest box quickly and neatly, the dancer, 

 it would seem, must have excellent sight. But careful obser- 

 vation of its behavior modifies this inference. For it appears 

 that a pair of mice dancing together, or near one another, 

 sometimes collide, and that it is only those holes with which 

 the animal is familiar that are entered skillfully. In fact, 

 the longer one observes the behavior of the dancer under 

 natural conditions, the more he comes to believe in the im- 

 portance of touch, and motor tendencies. Sight, which at 

 first appears to be the chief guiding sense, comes to take a 

 secondary place. In this chapter it is my purpose to show 

 by means of simple experiments what part sight plays in the 

 dancer's life of habit formation. 



The evidence on this subject has been obtained from four 

 sources: (i) observation of the behavior of dancers in their 

 cages; (2) observation of their behavior when blinded; 

 (3) observation of their behavior in a great variety of dis- 

 crimination experiments, many of which have already been 

 described ; and (4) observation of their behavior in labyrinth 

 experiments which were especially planned to exhibit the im- 

 portance of the several kinds of vision which the dancer 

 might be supposed to possess. The evidence from the first 

 three of these sources may be presented summarily, for much 



178 



