76 The Dancing Mouse 



The females, especially during periods of sexual excitement, 

 are much more likely to squeak than the males. At such 

 times they give their shrill cry whenever they are touched by 

 another mouse or by the human hand. A slight pinching of 

 the tail will frequently cause the female to squeak, but the 

 male seldom responds to the same stimulus by crying out. 

 The most satisfactory way to demonstrate the existence of a 

 voice in the male is to subject him to the stimulating effect 

 of an induced current, so weak that it is barely appreciable to 

 the human hand. To this unexpected stimulus even the 

 male usually responds by a sudden squeak. There can be 

 no doubt, then, of the possession of a voice by both males 

 and females. The males may be either less sensitive or less 

 given to vocal expression, but they are quite able to squeak 

 when favorable conditions are presented. The possession of 

 a voice by an animal is presumptive evidence in favor of a 

 sense of hearing, but it would scarcely be safe to say that 

 the mice must be able to hear their own voices. Cyon, how- 

 ever, thinks that some dancers can. What further evidence 

 is to be had ? 



Although they obtained no visible motor reactions to such 

 noises as the clapping of the hands, the snapping of the 

 fingers, or to the tones of tuning forks of different pitches 

 and the shrill tones of the Galton whistle, Alexander and 

 Kreidl (i p. 547) are not convinced of the total deafness of 

 the dancer, for, as they remark, common mice which un- 

 doubtedly hear do not invariably respond visibly to sounds. 

 Furthermore, the anatomical conditions revealed by their 

 investigation of the ear of the dancer are not such as to 

 render sensitiveness to sounds impossible. They recognize 

 also that the existence of the ability to produce sounds is an 

 indication of hearing. They have no confidence in the re- 

 sults reported by Cyon, for they feel that he did not take 



