United St-ates Department of the Intarior 



Oscar Ip Ciiapman, Secretary 



Fisli and Wildlife Serwice 



Albert M. Day, Directed 



Special Scientific. Sepcr*. =■ Pisheries 

 No. 53 



SEASOUAL YAEIATIONS IN TOXICITY OF BUTTER CLAMS 

 PSOM SELBGTED ALASKA BEACHES 



By J&im S. Chasnibers a^d 

 Harris W, Magnassoa 



* Chemist, Branch of Commercial Fisheries 



** Chemist, Branch of Commercial Fisheries, formerly Fishery- 

 Products Laboratory , Ketchikan, Alaska, now Fishery 

 Technological Laboratory, Boston, Massachusetts 



Washingtoa, D. C, 

 August 1950 



