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question, the occurrence of a flood on the river, for this not only removes most 

 of the causes tending to produce it, but also carries ofif the poor weak afflicted kelts 

 into sea water, where many may arrive dead, no doubt, but where others not so 

 badly affected get a chance of recovery. It was a flood of this character that put 

 an end to the disease in the river Wye in the month of INIay, during the epidemic 

 this year. 



As a general conclusion it may be stated, that the disease which kills the 

 salmon is now well proved to be the fungus Saprolegnia ferax. It is this, and this 

 alone, which destroys the fish by its rapid development on the skin. It attacks 

 weak or injured fish by preference, and they have less power of resisting the 

 growth of the fungus, but it is yet capable of attacking salmon which are in the 

 very best condition of health and strength when just fresh from the sea, and of des- 

 troying them in a very few days. Professor Huxley suggests the possibility that 

 some rootlets or mycelia of the disease may remain from a former attack, but too 

 deeply seated to have been eradicated by the beneficial effect of the salt water, 

 but as yet there is no proof of this. The cause of the appearance and rapid 

 growth of the fungus has yet to be discovered, but if one thing is more clear than 

 another it is that river pollution does not produce it. The same wonderful mys- 

 tery attends the development of this microscopic fungus as does that of many 

 others, which, extremely minute as they are, yet by their rapid production pro- 

 duce the greatest changes in organic nature. Their prevalence is possibly due to 

 meteorological causes not yet fully appreciated. The life-history of some of them, 

 however, as that of the funguses which cause fermentation ; of the fungus Pero- 

 nospora which affects the potato ; of muscardine (Botrytis hassiana), the fungus 

 which destroys the silkworm ; and now, too, we may say the same of Saprolegnia 

 ferax which kills salmon ; and of some others also ; is beginning to be under- 

 stood, and as knowledge further advances, the means of checking their production 

 will doubtless be increased. It would be valuable to di.scover the habitat of the 

 "resting spore," and some practicable system of exterminating it, and otherwise 

 diminishing the development of a disease which has so many methods of repro- 

 duction. Persevere then, oh Woolhopeans ! in the study of the minute funguses 

 which has already given so much renown to your Club ! Take warning, oh fisher- 

 men ! Injure the fish as little as may be possible ! Use your nets sparingly in 

 the early season of the year, when the exhausted fish are on their way back to 

 the sea ; and when you do take them, handle them tenderly, as if you loved them. 

 And, lastly, oh conservators and legislators ! spare no efforts to purify the rivers. 

 Remove without delay from your rivers all dead, and all badly diseased fish, 

 and bury them deeply, or far better still, completely annihilate every spore by 

 cremating. them. Knowing as much as we do about the prolonged dormancy of 

 resting spores, knowing how disturbed the ground may be by the burrowings of 

 rats, moles, earthworms, &c., and that latent spores may thus, at some future 

 period, be again brought to the surface of the ground, and, upon the advent of the 

 next flood or shower, washed into the river, there again to re-exercise their deadly 

 influence ; we should recommend providing against this contingencj' by a system 

 of cremation. Let the bailiffs be supplied with a few faggots wherewith to form 



