OYSTERS AND DISEASE. 
I,— INTRODUCTION. 
This research \va.s commenced three years ago, and has been carried on inter- 
mittently in the intervals of other work. One of us (\V. A. II.) had been working for 
some years previously at Fishery questions for the Lancashire Sea-Fisheries Committee, 
and so had become cognisant of the methods of growing and bedding Oysters on our 
coasts, of their variations in condition and colour, and of the want of exact knowledge 
as to their connection with disease. As this was clearly a matter of combined Natural 
History and Bacteriology, he proposed to his colleague (R. B.) that they should under- 
take a joint investigation of the structure and life-conditions of the Oj-ster in healthy 
and unhealthy environments — a matter of importance both for the Oyster industries 
and for public health. 
A preliminary paper on the plan of work and on the first experiments was laid 
before Section D. (Zoology and Physiology) at the Ipswich meeting of the British 
Association (September, 1895). This led to the formation of a small Committee to 
carry on the work, with the help of a grant of ; and interim reports were sub- 
mitted at the Liverpool (1896) and Toronto (1897) meetings. The final report of that 
Committee was given to the I^ritish Association at Bristol last autumn. 
In these reports, necessarily brief and without illustrations, it has only been 
possible to give a summary of results ; and, in the summer of 1897, one section of the 
subject — the presence of copper in the leucocytes of certain Oysters — was treated by us 
in a preliminary manner in a short communication to the Royal Society.* We propose 
now to give a full account of the evidence upon which our various conclusions, some 
of which were announced in these preliminary reports, are based, along with a discussion 
of our results and those of other workers, both from the purely scientific and also from 
the Fisheries and the Sanitary points of view. 
One member of our British Association Committee, Dr. Charles Kohn, Lecturer 
in Chemistry at University College, Liverpool, has given us considerable help from time 
to time in discussing with us the chemical aspects of the work, and in making analyses 
of different kinds of Oysters. We have also had the advantage of advice from our 
* Proc. R. S., vol. LXII., No. 379, p. 30. 
