562 REPORT— 1898. 



occurs in Mollusca living in pure sea- water. The natural inference that 

 the presence of the Colon bacillus invariably indicates sewage contamina- 

 tion must, however, not be considered established without further 

 investigation. 



8. The Colon group may be separated into two divisions — (1) those 

 giving the typical reactions of the Colon bacillus, and (2) those giving 

 corresponding negative reactions, and so approaching the typhoid type ; 

 but in no case was an organism giving all the reactions of the B. ti/phosu.s 

 isolated. It ought to be remembered, however, that our samples of 

 oysters, although of various kinds and from different sources, were in no 

 case, so far as we are aware, derived from a bed known to be contaminated 

 or suspected of typhoid. 



9. Consequently, as the result of our investigations, and the considera- 

 tion of much evidence, both from the oyster-growers' and the public health 

 oflScers' point of view, we beg to recommend — 



(a) That the necessary steps should be taken to induce the oyster 

 trade to remove any possible suspicion of sewage contamination from 

 the beds and layings from which oysters are supplied to the market. 

 This could obviously be effected in one of two ways, either (1) by 

 restrictive legislation and the licensing of beds only after due inspec- 

 tion by the officials of a Government Department, or (2) by the 



. formation of an association amongst the oyster-growers and dealers 

 themselves, which should provide for the due periodic examination of 

 the grounds, stores, and stock by independent properly qualified 

 inspectors. Scientific assistance and advice given by such inde- 

 pendent inspectors would go far to improve the condition of the 

 oyster beds and layings, to re-assure the public, and to elevate the 

 oyster industry to the important position which it should occupy. 



(b) Oysters imported from abroad (Holland, France, or America) 

 should be consigned to a member of the ' Oyster Association,' who 



: should be compelled by the regulations to have his foreign oysters 

 as carefully inspected and certificated as those from his home layings. 

 A large proportion of the imported oysters are, however, deposited 

 in our waters for such a period before going to market that the 

 fact of their having originally come from abroad may be ignored. If 

 this period of quarantine were imposed upon all foreign oysters a 

 great part of the difliculty as to inspection and certification would be 

 removed. 



(c) The grounds from which mussels, cockles, and periwinkles are 

 gathered should be periodically examined by scientific inspectors in 

 the same manner as the oyster beds. The duty of providing for this 

 inspection might well, we should suggest, be assumed by the various 

 Sea Fisheries Committees around the coast. 



APPENDIX. 



JS^otes on the Occurrence of Iron and of Copijcr in certain OfjSters. 



By Charles A. Kohn, B.Sc, Ph.D. 

 The investigations of Professors Herdman and Boyce on the life con- 

 ditions of oysters, ^yllich have been in progress since 1895, have pointed to 

 the desirability of ascertaining the quantities of iron and of copper they 

 may contain under either normal or abnormal conditions. 



