Issued April 19, 1911. 



U. S. DEPARTMENT OF AGRICULTURE, 



BUREAU OF CHEMISTRY -BULLETIN No. 136. 



H. W. WILEY, Chief of Bureau. 



SHELLFISH CONTAMINATION FROM SEWAGE- 

 POLLUTED WATERS AND FROM 

 OTHER SOURCES. 



By 



GEORGE WHITFIELD STILES, JR., 



In Charge, Bacteriological-Chemical Investigations. 



WASHINGTON: 



GOVERNMENT PRINTING OFFICE. 

 1911. 



