EXCITATION AND CONDUCTION 



case the decrease of carbon dioxide production is decided. 

 Table VIII illustrates quantitatively the difference in 

 carbon dioxide production under these different con- 

 ditions. The interesting results with 3 per cent and 

 4 per cent solutions will be considered later. 



TABLE VIII 

 EFFECTS OF CHLORAL HYDRATE ON CLAW NERVE OF SPIDER CRAB, Libinia canaliculata 



Is the decrease of carbon dioxide due to narcosis? 

 The results given above establish beyond a doubt that 

 during treatment with narcotics, in concentrations which 

 produce a reversible loss of irritability, the carbon 

 dioxide output of a nerve is greatly reduced. The 

 differences thus produced are far beyond the limits 

 of experimental error and there can be no suspicion that 

 the phenomenon is the result of faulty observation. The 

 question might be raised, however, whether this diminu- 

 tion is directly related to the narcosis, or whether it 

 might not be due to some factor casually introduced 



