110 MATHILDE L. KOCH AND OSCAR RIDDLE 



7. The significance of the results obtained in the present and 

 former series of analyses has been reviewed. The evidence war- 

 rants the conclusion that chemical differentiation, probably rep- 

 resented largely by the relative abundance of the myelin, does 

 not proceed as rapidly in the brain, and more particularly in the 

 cerebellum-medulla, of ataxic birds as in the brain of normal 

 birds. 



LITERATURE CITED 



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