105 
circumstances that deprive its presence of any special 
significance. 
I am not arguing against the value of bacteriology, but 
against a possible abuse of the method, and in favour of a 
much wider investigation in which the laboratory work will 
in all cases be supplemented, guided and inspired by the 
marine biologists’ work in the field. The case of each 
estuary, bed, or laying must be regarded as a separate 
problem to be solved with a full knowledge of all the local 
conditions. 
