Structural Peculiarities and Behavior 53 



in general the functional facts lead the investigator to expect 

 modifications of the sense organs rather than their absence. 



I shall now give an account of the results of studies concern- 

 ing the structure of the ear and brain of the dancer. Since 

 the descriptions given by different anatomists contradict one 

 another in many important points, the several investigations 

 which have been made may best be considered chronologi- 

 cally. 



Bernhard Rawitz (25 p. 239) was the first investigator 

 to describe the structure of the ear of the Japanese or Chinese 

 dancers, as he calls them. The definite problem which he 

 proposed to himself at the beginning of his study was, what 

 is the structural basis of the whirling movement and of the 

 deafness of the mice ? 



In his first paper Rawitz described the form of the ears 

 of five. dancers. His method of work was to make micro- 

 scopic preparations of the ears, and from the sections, by 

 the use of the Born method, to reconstruct the ear in wax. 

 These wax models were then drawn for the illustration of the 

 author's papers (Figures 8, 9, 10). 



The principal results of the early work of Rawitz are 

 summed up in the following quotation from his paper: "The 

 Japanese dancing mice have only one normal canal and that 

 is the anterior vertical. The horizontal and posterior ver- 

 tical canals are crippled, and frequently they are grown 

 together. The utriculus is a warped, irregular bag, whose 

 sections have become unrecognizable. The utriculus and 

 sacculus are in wide-open communication with each other 

 and have almost become one. The utriculus opens broadly 

 into the scala tympani, and the nervous elements of the 

 cochlea are degenerate. 



"The last- mentioned degeneration explains the deafness 

 of the dancing mice; but in my opinion it is a change of 



