214 PROTOPLASMIC ACTION AND NERVOUS ACTION 



In this case, the ratio of about 3 : i between successive 

 members is well shown. In other cases this relation is 

 obscured by chemical and other factors; an instructive 

 instance is the relatively high toxicity of methyl as 

 compared with ethyl alcohol, apparently a consequence 

 of the special properties of the former's oxidation 

 products, formaldehyde and formic acid. Fiihner cites 

 other cases showing a similar regularity; he finds, 

 however, that in tissues with high lipoid-content, such 

 as the vertebrate central nervous system, the higher 

 members of certain series (alcohols) are more effective 

 than would be expected from this simple rule. This 

 discrepancy he ascribes to the larger proportion of 

 organic solvent (Hpoid) in such tissues; thus, in the 

 adult frog the divergence from the 3 : i ratio is greater 

 ( = ca. 4:1) than in the tadpole ( = 2.9:1); this difference 

 is apparently referable to the increase in lipoid constitu- 

 ents as the central nervous system develops.^ It seems 

 probable that in lipoid-rich tissues the lipoid-solvent 

 factor becomes relatively important in comparison with 

 the capillary constant factor. 



The relatively great solubility of many anaesthetic 

 organic compounds in protein-containing systems defi- 

 cient in Hpoid (serum, finely divided muscle, etc.) has 

 been attributed by Moore and Roaf^ to the formation 

 of chemical combinations with the protein; but since 

 all such systems are undoubtedly polyphasic, and since 

 chemical combinations (in the stoichiometric sense) of 

 hydrocarbons (like CHCI3, benzol, etc.) with proteins are 



^ Fiihner, Z. Biol., LVII (191 2), 465. 



2 Moore and Roaf, Proceedings of the Royal Society, B, LXXIV 

 (1908), 382; LXXVII (1906), 86. 



