SEA-FISHERIES LABORATORY. 369 



Investigations have not, so far, been made in the Irish. 

 Sea, and we have thns no means of ascertaining how far 

 the pollution in any specific case is due to this supposed 

 general contamination. It is because one is unable 

 precisely to separate the effects of this general (and 

 probably harmless) contamination from local and always 

 potentially dangerous pollution that there must frequently 

 be difficulty in interpreting such results as this analysis 

 gives. A thorough examination of the distribution of 

 colon bacilli in the coastal waters of Lancashire would 

 undoubtedly be of practical value. 



