16 LABORATORY MOUSE 



mice. 1 Thus national tradition provided a psychological 

 attitude among the Japanese most favorable for the develop- 

 ment of the mouse as a fancy animal. In Japan today the 

 mouse fancy is well developed, having thriven for at least 

 three centuries. 



It is difficult to ascertain how long varieties of the house 

 mouse have been recognized in China. The word for white 

 mouse is ancient, and that for spotted mouse appears in the 

 earliest Chinese lexicon, written 1100 B.C. The waltzing 

 variety has been known since 80 b.c. That the Nipponese of 

 Yokohama and elsewhere zealously collected new varieties 

 in foreign lands is shown by the fact that they call a mouse 

 bearing certain markings the "Nanking Mouse" (162), 

 while the Chinese fanciers of Shanghai near Nanking deny its 

 origination and call it the foreign mouse. The Japanese 

 waltzer was undoubtedly derived, at least in part, from Mus 

 bactrianus (wagneri) of Tibet, as pointed out by Bowdler 

 Sharpe (158) in 1912. Moreover, Mus musculus proper is not 

 native to Japan. Perhaps the Japanese procured the Euro- 

 pean M. musculus varieties from Portuguese traders. 



The Japanese had in their fancy such varietal characteris- 

 tics as albinism, non-agouti, chocolate, waltzing, dominant 

 and recessive spotting, and possibly blue dilution, pink- 

 eyed dilution, and lethal yellow. 



Something over a hundred years ago several of these 

 fancy varieties of the house mouse were taken from Japan 

 to Europe by British traders, and only a few decades ago did 

 muriculture spread to America. 



During the nineteenth century a number of European 

 zoologists bred fancy mice for scientific investigation of the 

 inheritance of varietal characters. They accumulated valu- 

 able information, but the meaning of these data remained 

 unknown until the rediscovery of Mendel's Law of Heredity 

 in 1900 (33). 



1 The Japanese have a saying that white mice are good and honest while dark 

 ones are wicked and dishonest. Believing that good overcomes evil, some Japanese 

 bring white mice into their houses in order to drive out the wild gray ones. 



