70 The Dancing Mouse 



turbance. With the same possibility in mind the author of 

 "Fancy Varieties of Mice" writes: "These quaint little 

 creatures make amusing pets for any one who is not scientific, 

 or very fond of knowing 'the reason why.' In their case, 

 the reason of the peculiarity which gives them their name 

 is rather a sad one. It is now pretty conclusively established 

 that they are no more Japanese than they are of any other 

 country in particular, but that the originators of the breed 

 were common fancy mice which were suffering from a disease 

 of the brain analogous to the 'gid' in sheep. In the latter, 

 the complaint is caused by a parasite in the brain; in the 

 case of the Waltzing Mouse, it is probably due to an hereditary 

 malformation therein. Be this as it may, the breed is now 

 a firmly established one, and the children of waltzing mice 

 waltz like their parents" (32 p. 45). Although it is quite 

 possible that peculiarities in the central nervous system, 

 rather than in the peripheral nervous system, may be respon- 

 sible for the forms of behavior exhibited by the dancer, it 

 must be remembered that no such peculiarities have been re- 

 vealed by the examination of the central nervous system. 

 The old fancier has neither better nor worse grounds for his 

 belief than have Panse and Kishi. 



So far as the reliability of the anatomical work which has 

 been discussed is in question, it would seem that Rawitz's 

 results are rendered somewhat unsatisfactory by the careless- 

 ness of Cyon in fixing the materials ; that Panse's descriptions 

 and comparisons are neither careful nor detailed enough to be 

 convincing ; that the work of Alexander and Kreidl, as well as 

 that of Kishi, gives evidence of accuracy and trustworthiness. 

 The fact that the statements of Alexander and Kreidl frequently 

 do not agree with those of Kishi proves that there are serious 

 errors in the work of one or another of these investigators. 

 Cyon's discussion of the anatomy of the dancer is not to be 



