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chapter of inquiry, though up to the present he had not 

 been able to make any experiments in regard to it It 

 was very possible that any superabundance of lime in the 

 caustic state might have a very considerable effect in bringing 

 about the development of the disease. In the first place 

 fungi of all kinds were extremely sensitive to small degrees 

 of acidity and alkalinity of water, and secondly the 

 condition of acidity and alkalinity was extremely likely, 

 however small its extent might be, to have a very definite 

 effect on the epidermis of the fish. This, therefore, 

 suggested a line of investigation, which was likely to prove 

 extremely fruitful. As to the use of salt, he believed that was 

 an absolute remedy, and there seemed to be a consensus of 

 opinion to that effect. Some experiments carried out by 

 the Conservators of the Tweed showed that fish, even in 

 an advanced stage of the disease, when confined in cribs in 

 tidal waters, if they did not die of the confinement, got 

 well of the disease. Although there was one doubtful 

 case on record of disease showing itself on fish in salt 

 water, unfortunately the evidence that the disease was 

 caused by Saprolegnia was wanting ; and up to the present 

 he had never been able to see any sufficient ground for 

 believing that Saprolegnia could appear on any fish in 

 salt water. Finally he would say one word about fish 

 parasites. The fuss made about the parasites of fish was 

 really very extraordinary. The lower animals, and fish 

 especially, were not at all particular about parasites. 

 Parasites were regularly and constantly found in particular 

 parts of their organisms, and might rather be considered 

 sharers of their repast than anything else, simply taking toll 

 of whatever came in their direction. In most cases, there 

 there was not the least evidence that these parasites had any 

 effect on the welfare of the fish. He remembered that two 



