43 



of the season (December till April) are perfectly capable 

 of living in sterile sea water and to retain their normal 

 character and aspect in perfect condition. In the second 

 place, the oysters after infection with even large numbers 

 of the B. typhosus remain to the eye indistinguishable in 

 all respects from non-infected normal oysters. This latter 

 point is of course important from a practical point of 

 view, inasmuch as oysters which are so infected would 

 in the ordinary course of things remain undetected. So long 

 as the oyster shell is well closed and the oyster on opening 

 would present the normal appearance of colour, juiciness 

 and plumpness, it would naturally pass as " of good quality." 

 As has been pointed out on a former page, the longer 

 persistence of the B. typhosus in oysters out of the water 

 makes such oysters dangerous to a higher degree than when 

 they are kept in the water. Now, it is common knowledge 

 that on many occasions oysters when taken from an in- 

 fected laying or, at any rate, from a polluted locality are 

 packed and kept in barrels, tubs, or the like, sometimes for 

 short, sometimes for long periods. This applies, of course, 

 in a conspicuous degree to oysters coming into England 

 from distant countries America, France, Holland but it 

 applies also to many oysters coming from distant localities 

 in England into London or other large towns, viz., they are 

 kept out of the water, i.e., in " dry " state, sometimes for 

 several days before they reach the consumer. From the 

 experiments we have described it must be obvious that this 

 practice should be done away with, for there is no difficulty 

 whatever in any part of England or Holland to keep oysters 

 in clean sea water, which can be frequently changed ; if we 

 can do so at a very small cost indeed in a laboratory in 

 London, I do not see that the same thing should not be 

 possible in seaside and other places ; all that seems required 

 is a sufficiently large receptacle, which can be thoroughly 

 brushed out and scalded with boiling water, and a sufficient 

 supply of clean sea water. We get here delivered in the 

 laboratory five gallons of sea water (23 litres) at the price of 

 sixpence, that is to say, sufficient water to give to each four 



