22 BACTERIOLOGY OF THE OYSTER. 



transferred with sterile forceps to another fermentation tube, care 

 being taken not to touch the parts where the incision is made with 

 the fingers or to contaminate it in any way. This procedure i& 

 repeated until 10 individuals have been tested from each sample jar. " 



It would appear that the work of Clark has had wide influence in 

 determining the method of shellfish analysis now in use in this country. 

 So far as the writer is aware and so far as the literature at hand shows, 

 the only part of the oyster used for bacteriological analysis for some 

 years has been the shell liquor. The "Committee on Standard 

 Methods of Shellfish examination" appointed by the American 

 Public Health Association has recommended the use of the shell 

 liquor only. So far as a perusal of the recent literature is concerned 

 no one has questioned the advisability and propriety of using the shell 

 liquor alone for analytical purposes except Gorham^ upon results 

 obtained by the writer in the laboratory of Brown University. 



It will be noticed in all the work cited in which parts of the intestine 

 have been used for analysis, except in the case of Fuller, no mention 

 has been made of trying to avoid taking bacteria from the outside 

 of the oyster as well. In the writer's opinion a great many of the 

 bacteria alleged to have been found in the intestinal tract have come 

 from the mucus on the outside of the body. There is no doubt that 

 the intestine of the oyster does contain bacteria of sewage origin, 

 but the mucus on the outside of the bod}^ is much more likely to 

 contain such bacteria. 



BACTERIOLOGY OF THE SHELL LIQUOR AND ^^WASHINGS'^ 

 FROM THE BODY OF THE OYSTER. 



A matter of great interest to the writer is that in all the work done 

 upon oysters experimentally and otherwise no one has mentioned the 

 mucus of the oyster or apparently realized that it plays any part in the 

 bacteriology of the oyster. 



The matter of the mucus in the oyster juice and on the oyster's body 

 appears so self-evident that it seems impossible that it should have 

 been entirely neglected. This mucus serves at least two purposes. 

 (1) It acts as a protection to the body of the oyster and protects it 

 from the deleterious effects of sea water in just the same way as the 

 mucus of the dog fish and other selachians protects their skin from 



^Report of Commissioners of Shell Fisheries, State of R. I., 1914. 



