SPONTANEOUS MOVEMENTS IN LARY.K. 42! 



appears to bring into play a secondary reserve mechanism which 

 gives it a compensatory capacity not possessed by the neuro- 

 muscular system through which body movements are produced. 



7. Toad fish larvae are much more resistant to asphyxial 

 conditions than adults. 



8. It is suggested that the migration of fishes in a H-ion 

 gradient is probably conditioned by the effect of acid substances 

 on the endoi;<-n(>ii> body movements. 



9. It is suggested that stimulation by variation in the concen- 

 tration level of metabolites produced inside the body may be 

 the source of endogenous (spontaneous) movements. 



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 Ahlfeld, F. 



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 28 



