CONTENTS. 



Page. 



Introduction 7 



Experimental investigations 9 



Plan of work 9 



Procedure for bacteriological examination 9 



Collection and shipment of samples 9 



Preparation of samples of shellfish 10 



Media employed 11 



Plating samples 11 



Water 11 



Oysters 12 



Identification of organisms 12 



Pure cultures 12 



Bacillus enteritidis sporogenes determination 13 



Description of isolated organisms resembling Bacillus typhosus 13 



General characteristics of the Bacillus coli organisms isolated 14 



Sources of contamination 15 



Location of oyster beds 15 



Bacteriological results on shellfish and sea water 16 



Comparison of results obtained on samples from known sanitary 



and insanitary grounds 19 



Floating oysters in polluted water 20 



Inspection data 20 



Laboratory results on floated oysters 24 



Discussion 26 



Storage of oysters 28 



Spoilage due to length of time out of water 28 



Diseased and green oysters 29 



Handling of shucked oysters 30 



Insanitary oysterhouses 31 



Washing oysters 33 



Character of containers 35 



Insufficient cooling 36 



Souring due to age 36 



Graphic presentation of results by two methods of handling 37 



Cooking tests 37 



Collated opinions on sewage contamination : 40 



Transmission of disease by infected shellfish 40 



Presence of Bacillus coli and Bacillus typhosus in oysters 42 



Vitality of Bacillus coli and Bacillus typhosus in sewage-polluted water and 



in shellfish 44 



Significance of sewage organisms in food supplies 45 



Summary 48 



Bibliography 50 





