73 



not manufactured, and sheep-wash would be in the refuse water. If the EDINBURGH. 



raw wool is washed in the river it must be very bad for the fish. Sewers and 



factories should be attended to. 



The disease is virulent in pure and in impure water. If there were no 

 sewers and no factories the dead fish alone would make the water stink. Would 

 bury a fish half dead. Would leave the condition of fish to the judgment of 

 the local watchers. 



[Drawings produced of fungus, published in a Polish pamphlet — " Pathologia 



Ryb " — by Michal Girdwoyn.] 

 They are certainly S.ferax. 



Has never bred J ish. Cannot speak as to young salmon with gill fever, and 

 fungus stopping 1 p their gills. 



A spore float; in the river like a thistle-down in the air, and will alight 

 on fish. The sp -rules will float downwards, and adhere more readily to the 

 unsealed parts of the fish. 



Is quite certain that all the cases of aquarium fungus that he has seen are 

 not S.ferax, but a confervoid fungus. The filaments maybe seen with the 

 naked eye, but the spores cannot be seen. 



A duck might carry the spores. Has seen hooded crows feeding on dead 

 fish, but cannot see how they could bring the spores into the water. The wild 

 duck's foot is so large that many spores might adhere to it. One hundred 

 spores might be on the point of a needle. 



Has picked up grayling dead in the Clyde. There is no saprolegnia there. 

 If there be truth in the bird theory, the Clyde would probably have been 

 affected, but the birds might fly to one river and not to another. 



[Produces a specimen of the head of a fish diseased with fungus.'] 

 Thinks the fungus is the disease, and not an aftergrowth on a previously 

 diseased surface. The fish's skin is quite perfect, without any sore. There is 

 fungus all over it and on the lips. The skin of the lips is eaten away and in 

 shreds. 



[Produces the tail end of the same fish.] 

 The fungus is transparent, and the scales can be seen below quite whole. The 

 fungus is not superadded to a disease. 



Kelts have been known for hundreds of years to die aftsr spawning. Attri- 

 butes this to the labour of spawning, to the want of food, and the emaciation 

 caused by the absorption of fat for the formation of ova or milt. 



The fish make their redds with their body. Never saw fungus on ulcerated 

 sores in kelts. 



Never saw specimens of sea fish with fungus. Believes salt will kill the 

 fungus. The fish going to the sea will probably be cured. 



His minnows ate the fungus. They were among the fungus from the begin- 

 ning of May to 18th June. The fungus was removed then, as the fish were 

 not affected by it. The fungus may have been dead when he put it in, but did 

 not know it was dead. The fungus on the fish sent to him was barren. The 

 experiment with the minnows was futile. Cannot say when the fungus 

 reproduces. Got grayling from the Tweed with living fungus in April. Saw 

 the spores moving, and saw them become stationary, and the filaments grow 

 from them. The cilia had disappeared. This all took place in an hour. To 

 the eye the growth of a filament under the microscope gives an impression 

 of length equal to half an inch. 



The oospores might lie quiescent for many years. When stimulated into 

 great reproductive power, a numerous crop of fruit would grow from them. 

 This fruit (zoospore) is what causes the plague. It produces the plant, and 

 the plant produces the oospore. After the plant is dead the disease must cease 

 till the activity of the oospore is kindled. 



Fungi are capable of producing zoospores. Unless the oospores are 

 highly stimulated the fungi are barren. The zoospores are only an aggrega- 

 tion of granules. The oospore has a cell-wall and a nucleus. 



Sir Robert Christison, Bart., Moray Place, Edinburgh, Honorary Vice- 

 President of the Royal Society. — Has paid attention incidentally to the salmon 

 disease. Has received specimens of diseased fish from the Nith and Tweed. 

 They were both kelts, and perfectly sound fish. Nothing was to be seen 

 outside except the fungus. Sent them to Mr. Stirling, who showed that 



