354 Journal of Comparative Neurology. 



That the results for the influence of season upon growth 

 are no more decided, may be due to two causes. 



The January frogs were taken from those which had been 

 collected in the autumn and kept at the ordinary basement tem- 

 perature. The results for these frogs might have been different 

 had normally hibernating animals been available. 



But again, even if growth does cease during the winter 

 months, it is by no means certain that counts made then should 

 show a much less percentage of fibers which have not yet 

 reached their destination than counts made during other months. 

 Fibers which start in the warmer months may not complete 

 their extension during those months and thus, though checked 

 during the colder months, would still affect the counts made 

 during this season. 



X. Bibliography. 



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