CHAPTER XVIII 

 THE INHERITANCE OF FORMS or BEHAVIOR 



'IN a general way those peculiarities of behavior which 

 suggested the name dancing numse are inherited. Genera- 

 tion after generation of the mice run in circles, whirl, and 

 move the head restlessly and jerkily from side to side. But 

 these forms of behavior vary greatly. Some individuals 

 whirl infrequently and sporadically ; others whirl frequently 

 and persistently, at certain hours of the day. Some are 

 unable to climb a vertical surface ; others do so readily. Some 

 respond to sounds; others give no indications of ability to 

 hear. I propose in this chapter to present certain facts con- 

 cerning the inheritance of individual peculiarities of behavior, 

 and to state the results of a series of experiments by which I 

 had hoped to test the inheritance of individually acquired 

 forms of behavior. 



My study of the nature of the whirling tendency of the 

 dancer has revealed the fact that certain individuals whirl to 

 the right almost uniformly, others just as regularly to the 

 left, and still others now in one direction, now in the other. 

 On the basis of this observation, the animals have been classi- 

 fied as right, left, or mixed whirlers. Does the dancer 

 transmit to" its offspring the tendency to whirl in a definite 

 manner ? 



Records of the direction of whirling of one hundred in- 

 dividuals have been obtained. For twenty of these mice 

 the determination was made by counting the number of com- 



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