492 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



5- The Roosebeck and Barrow Channel Mussel Beds. 



I have already described the natural conditions on 

 and about Hoosebeck Scar. It is evident, from a careful 

 consideration of these conditions, that the degree of 

 contamination to which it is exposed may safely be 

 neglected. There is no evidence that shell-fish from this 

 ground have ever been the means of transmitting disease. 

 The analysis made by me on July 27th of this year 

 showed that intestinal bacteria were absent in l/10th 

 part of a mussel, and this was an average result : it really 

 means that in l/10th part of each of five mussels 

 taken indiscriminately from all parts of the bed there 

 could be detected no contamination. This result may be 

 accepted without reserve, for a negative reaction in 

 MacConkey's bile-salt broth indicates that no bacteria 

 resembling B. coli could be present in the material 

 examined. On November 1, however, a positive result 

 was obtained. In this analysis a mean of 310 " sewage " 

 bacteria per mussel was found. But having regard to 

 the natural conditions indicated above, this result cannot 

 be accepted without qualification. Obviously, it is 

 desirable that the bacteria found in such an analysis 

 should be subjected to much closer scrutiny. The case 

 is one, obviously, for the rigorous investigation of the 

 characters of the organisms, for we cannot believe that 

 they are to be regarded as typical B. coli. I hope to 

 make this more detailed investigation later. In the 

 meantime I have no hesitation in describing these mussels 

 as free from dangerous contamination. 



Neither can one have any hesitation in saying that 

 mussels from Barrow Channel should, on no account, be 

 used as human food. The conditions here are such as 

 must lead to serious contamination. I have made no 



