Z BULLETIN OF THE BtlREAU OF FISHERIES 



as the cause of infectious diseases, a French physician, Pasquier, attributed the 

 epidemic of intestinal illness to the eating of raw oysters taken from sewage-polluted 

 bottoms. Since 1816, the year when his investigation was made (Pasquier, 1818), 

 and up to the present tmie, oj'sters and other shellfish often were held responsible 

 for the outbreaks of acute gastrointestinal disturbances and typhoid fever. 



Realizing the danger to the public health brought about by the consumption of 

 infected oysters, and conceiving the damages to the oyster industry caused by the 

 loss of public confidence in the safeness of the oyster, the various States gradually 

 have placed the harvesting and handling of oysters under the supervision of the munic- 

 ipal and State health authorities and shellfish commissions. In 1909 the Federal 

 Government took a step in the same direction M-hen the United .States Department 

 of Agriculture, acting under the authority of the Federal food and drugs act, issued 

 Food Inspection Decision No. 110, which declared it to be unlawful to ship or to sell 

 polluted shellfish m interstate commerce. In the following year, by another act 

 (Department of Agriculture, Food Inspection Decision No. 121), it prohibited the 

 shipment or sale of oysters floated in polluted waters. In 1927 Food Inspection Deci- 

 sion No. 110 was reaffirmed and it was declared unlawful to ship or to sell in inter- 

 state commerce oysters or other shellfish that have been subjected to "floating" 

 or "drinkuig" in brackish water or water containmg less salt than that in which they 

 are grown. (Department of Agriculture, Food Inspection Decision No. 211). At 

 present all the oyster-producing States have adopted a system of issuing certificates 

 to the respective oyster growers and dealers under the supervision and with the 

 approval of the United States Public Health Service. According to this plan every 

 bed from which oysters are taken for the market is examined from a sanitary point 

 of view and must conform to the established bacteriological and chemical standards of 

 purity. 



The question of standards in the sanitary control of shellfish was much discussed 

 and is of great importance to the industry. For many years bactei'iologists were 

 using various schemes of bacteriological examination of the oysters, with the result 

 that various Federal, State, and municipal authorities gave preference to one or 

 another standard and enforced their regulations accordmgly. In 1922 the American 

 Public Health Association (Committee on Standard Methods for the Bacteriological 

 Examination of Shellfish, 1922) adopted a standard method for the bacteriological 

 examination of shellfish, which at present is widely though not universally employed 

 in the sanitary control of the shellfish industry. Briefly speaking, it consists in deter- 

 mining the relative abundance of Bacterium coli in the shell liquor of the mollusks and 

 expressing the results by an arbitrary numerical system known as the American 

 Public Health Association method of scoring oysters. The technical procedure con- 

 sists in making a composite sample from at least five oysters and incubating the 

 fermentation tubes filled with lactose broth with 0.1 and 0.01 cubic centimeter of 

 the composite liquor. The water required for dilution purposes is either sterile sea 

 water or tap water containing 2 per cent sodium chloride. For each dilution five 

 fermentation tubes are used; altogether 15 fermentation tubes are required for every 

 test. Upon the formation of gas, confirmatory tests are made in accordance with the 

 standard methods of water analysis. The presence of Bacterium coli in each tube, 

 if confirmed, is to be given the value representing the reciprocal of the greatest 



