SEA-FISHERIES LABORATORY. 133 



" 11. Experiments in feeding Oysters with weak solu- 

 tions of various copper and iron salts gave no definite 

 results, certainly no clear evidence of any absorption of 

 the metals accompanied by ' greening.' 



''12. Although we did not find the Bacillus typhosus 

 in any Oysters obtained from the sea or from the markets, 

 yet in our experimental Oysters inoculated with typhoid 

 we were able to recover the organism from the body of 

 the Oyster up to the tenth day. We show that the typhoid 

 bacillus does not increase in the body or in the tissues of 

 the Oyster, and our figures indicate that the bacilli perish 

 in the intestine. 



"13. Our experiments showed that sea-water was 

 inimical to the growth of the typhoid bacilli. Although 

 their presence was demonstrated in one case on the 

 twenty-first day after addition to the water, still there 

 appeared to be no initial or subsequent multiplication of 

 the bacilli. 



"14. In our experiments in washing infected Oysters 

 in a stream of clean sea-water the results were definite 

 and uniform ; there was a great diminution or total dis- 

 appearance of the typhoid bacilli in from one to seven 

 days. 



" 15. The colon group of bacilli is frequently found in 

 shell-fish as sold in towns, and especially in the Oyster ; 

 but we have no evidence that it occurs in mollusca living 

 in pure sea-water. The natural inference that the presence 

 of the colon bacillus invariably indicates sewage con- 

 tamination must, however, not be considered established 

 without further investigation. 



"16. 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 



