LIFE HISTORY OF THE SCAVENGER WATER BEETLE 

 HYDROUS (HYDROPHILUS) TRIANGULARIS, AND ITS 

 ECONOMIC RELATION TO FISH BREEDING : : : 



: : : : : : By Charles Branch Wilson, Ph. D. 



From BULLETIN OF THE BUREAU OF FISHERIES/ Voltiiiie XXXIX, 1923-24 

 Document No. 942 : : ; ; ; ; ; ; ; ; ; ; ; : ; : ; ; ; ; ; 



I 



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1923 



