60 



worms. But this method has its drawbacks from the difficulty of 

 transporting them over long distances, and could only be used 

 in favourable localities. The most effective as well as the quickest 

 method would be the drying process. • The oysters should be 

 removed from the beds, freed from mud by washing, and then 

 placed under a shed or cover of some kind, to protect them from 

 the sun's rays. The oysters should be spread out in thin layers, 

 and occasionally turned over, so as to ensure the thorough drying 

 of the shells externally. The process may be continued for ten 

 days or longer — if the oysters would stand it. They might after 

 wards be relaid on the beds, if suitable ground exists on which 

 to lay them — that is to say ground having a stony or shelly 

 bottom. If they are laid on a mud surface, they will very soon 

 be infested again. Another method which might be useful would 

 be to remove the oysters into prepared ponds, into which none 

 but moderately clear water is allowed to enter, or place them on 

 a sandy or pebbly beach in such a position that they would be 

 exposed to the sun, and get partially dry between every rise and 

 fall of the tide. No doubt if either course was adopted and 

 continued for some months, the worms already in the oysters 

 would be destroyed. The above mentioned remedies can only be 

 applied to oysters that are loose or attached to small objects, such 

 as shells, &,c. 



So long as oysters are cultivated on the bare surface of the 

 mud, they will be liable to the attacks of the worm ; but if some 

 solid substratum be provided for the spat to fix upon, and so 

 remove tliem from direct contact with the mud, the oysters will 

 have a chance of escaping the disease. 



It would be much to the advantage of men engaged in dredging 

 and of the les.sees, if they made themselves familiar with the 

 worm as it exists in the oyster in a living state. Tliis is com- 

 paratively an easy matter. All that is required is a small 

 magnifying glass and a vessel containing sea water. If a diseased 

 oyster is put in a shallow basin, the worms may be easily seen 

 projecting out of their tubes, and the pair of feelers playing to 

 and fro in search of food. If a practical knowledge be obtained 

 of the appearance of the diseased oyster and the living worm, 

 then the shells can be examined during any process carried on 

 for the destruction of the worms, and the observer will be able 

 to judge as to the effects of the remedy. If after placing a 

 diseased oyster in water, and after the lapse of some hours the 

 worms are not to be seen protruding their tentacles, it may be 

 safely concluded that they are dead ; but to make sure the oyster 

 should be opened carefully, and some of the worms taken out and 

 placed in a saucer of clean sea water, to see if there is any power 

 of movement left in them. 



