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bills of mortality. Our fishery doctors are of the same 

 mind as my friend. They are (or at any rate ought to be) 

 very much in doubt, and yet they continually want to play 

 trumps in the shape of stringent regulations and restrictions. 

 If I might tender a piece of advice, I would say don't 



DISCUSSION. 



Mr. FOLLETT asked why it was the diseased fish rose to 

 the surface of the water, he referred especially to gold fish 

 in artificial ponds. 



Professor HUXLEY said there was probably an increase 

 in the amount of air in the air-bladder, and very likely in 

 the viscera also produced by incipient putrefaction. 



Dr. SPENCER COBBOLD, having paid some attention to 

 parasites for a great many years past, had come there 

 hoping that Professor Huxley would open up the 

 whole subject, though contemplating its vast extent, 

 he felt that even he would find a difficulty in compassing 

 it. This not having been done, he would say a few words 

 on the parallelism between the role played by external and 

 internal fungi which might throw a little light on the general 

 subject. It was found on examination that certain fishes 

 were covered with Saprolegnia, and when they were dis- 

 sected they found no trace of internal parasites. In such 

 cases where death had supervened it was evidently due to 

 the presence of Saprolegnia alone, but in other cases a 

 number of internal parasites were also found ; and when 

 they took into consideration the fact that the role of the 

 internal parasite was so similar, with regard to the irrita- 

 tion it created to the external, the only difference being 

 that the irritation set up by the internal parasites was in 

 the muscles and viscera, it was impossible for any logical 



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