218 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
III.—Experiments on the Purification of Polluted 
Mussels. 
A series of experiments were made during 1908 with 
the object of ascertaining the conditions under which 
polluted mussels might be expected to cleanse themselves 
when placed in unpolluted water. On June 3rd I met 
Mr. Roberts, av Inspector of the Fishmongers’ Company, 
and we visited the Hstuary of the Conway River. The 
possibility of dealing with the polluted shell-fish of that 
area by re-laying them in the comparatively clean water 
at the mouth of the Estuary presented itself as the only 
way out of the apparent zmpasse, which has resulted from 
the complaints made as to the condition of the shell-fish 
taken from the river. The idea is, of course, no new one, 
and a long series of experiments made by Professor Klein, 
for the Fishmongers’ Company, seem to make it certain 
that an oyster or mussel! will evacuate the greater number 
of sewage organisms contained in it, 1f it be placed for 
several days in quite clean sea-water. Nevertheless, it 
appeared very desirable to make experiments in the 
locality itself. A place at the entrance to the Estuary, on 
the Morfa Beach, and about S.E. from the Perch, was 
selected by us, and I took samples of water from a pool on 
the foreshore about half-way up the beach, and also 
samples of water from the channel immediately adjacent. 
It seems probable that the water covering this part of the 
foreshore from about half-flood, or half-ebb, to high water 
would be unpolluted, or at least would be no more polluted 
than the sea generally along this coast—a degree of 
contamination which has, probably, no dangerous signifi- 
eance. On the other hand, the water in the Channel 
during the last of the ebb would be expected to be 
polluted to a much greater extent, for it would contain 
the drainage into the upper part of the Estuary. Three 
+ 3 
water samples were therefore taken :— 
