58 



Scientific Proceedings (27). 



observations. The snails of this genus are so distributed that each 

 archipelago and each island where they occur possesses unique 

 types, while often single valleys will comprise the habitat of a 

 species. Only two exceptions to the former statement are known. 



A detailed demonstration was made of the snails from 55 

 valleys of Tahiti, and from 19 valleys of Moorea, the two islands 

 of the Windward division of the Society group. The present 

 communication consisted chiefly of a description of the features 

 presented by the demonstrated valley populations. The general 

 conclusions of the survey are (1) that there is a general correlation 

 between geographical proximity or isolation on the one hand and 

 specific resemblance or divergence on the other hand ; (2) that 

 some species (r. g., P. hyalind) are wide-spread and relatively invari- 

 able, while other forms exhibit variations and mutations that seem 

 to be the antecedents of fixed independent varieties of the future ; 

 (3) and that variation does not seem to be referable to environ- 

 mental influences. 



32 (288) 



Note on the isolation of carnaubic acid from beef kidneys. 



By EDWARD K. DUNHAM. 



[From the Nezu York University and Bcllevue Hospital Medical 

 College, and the Rockefeller Institute for Medical Research^ 



A lipoid obtained from beef kidneys and having solubilities 

 similar to those of Liebreich's "protagon," yields, on cleavage 

 with alcoholic hydrochloric or sulfuric acid, an ester of carnaubic 

 acid, which separates on cooling. From this ester the free acid 

 may be obtained by saponification with sodium ethylate and de- 

 composing the resulting soap with a mineral acid. The free acid 

 and its ethyl ester are freely soluble in ether and chloroform ; 

 also, in hot alcohol, benzene, acetone, ethyl acetate or acetic acid, 

 but separate from these solvents on cooling. The acid melts at 

 72. 4°, the ethyl ester at 50°, both uncorrected. 



Analysis of the acid. It was purified by fractional precipitation 

 with magnesium acetate. The magnesium soap was decomposed 

 with hydrochloric acid. The acid was recrystallized from acetone : 



