138 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



Before relaying, five mussels from the sample were examined. 

 Three plates were made :- — 



1 /^0+h f ^ ate 1> 1,800 red colonies, 20 colourless colonies. 

 ' • , . i ,, 2, 1 The colonies were so numerous that the 

 ( ,, 3, J plates were uncountable. 



These mussels therefore contained at least 90,000 sewage 



bacteria each. 



First Sampling. Relaid for four tides. 



Plate 1, 370 red colonies, 15 colourless colonies. 

 „ 2, 627 „ 23 „ 



„ 3,432 „ 47 „ 



A considerable reduction of contained bacteria was 

 therefore experienced by these mussels. But reinfection 

 doubtless occurred, for the results are not satisfactory. The 

 place proposed was rejected as the result of the experiment. 



In these experiments the mussels were laid down on the 

 foreshore itself, on a beach of sand and gravel. There was 

 no enclosure of any kind. The places selected were out of 

 the main tidal streams, and were not exposed to any sea, 

 so that the mussels remained undisturbed — they had, in fact, 

 previously been employed by local fishermen for storing 

 mussels prior to sending them to market. The question then 

 arose as to the practicability of relaying mussels in places 

 like the Estuaries at Aberdovey and Barmouth, where the 

 tidal streams are rapid, where there is a certain exposure 

 to the sea, and where the shore slopes down very steeply 

 from high-water mark. Construction of enclosures, designed 

 to hold mussels while being cleansed, would be very difficult 

 and expensive in such circumstances ; and to meet this 

 difficulty, Mr. Gr. Hazlehurst, a member of the Committee, 

 made the very practical suggestion that a floating tank should 

 be used for relaying. A tank boat was therefore made, big 

 enough to hold several bags of mussels. The bow and stern 

 were open, being guarded by strong wire gauze, and movable 



