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EDINBURGH. Thinks the fungus is the disease. Thinks the spores of Saprolegnia ferax are 

 ■ more or less in the water always, and seize on any substance congenial to their 



growth. Cannot say if the fungus lives in salt water. Saw one or two bull- 

 trout lying dead, partly covered with water. Thinks they were killed by the 

 disease. 



It attacks the fish in the pools in low water. They could not get over the 

 shallows, and being prevented from getting up or down, they got into a weak 

 state and became attacked. Thinks the overcrowding of certain pools is the 

 cause, not the overstocking of the river. The fish can, he thinks, get up the 

 Whitadder, but is not sure. Has not heard of any new dams being erected 

 during the last 20 or 30 years. 



The bull-trout, being crowded in small pools, are predisposed to disease. 

 Thinks facilities should be given to fish to get down to the sea at all states of 

 tl'ie river. Speaks only of the Whitadder. Does not know the Blackadder. 

 Imagines the fish go up it. 



Thinks the value of the sea fishing has increased very much the last few 

 years. Many more fish are taken in the sea than formerly, owing to the 

 improved engines for taking them. 



A. B. Stirling, assistant curator of the Anatomical Museum, Edinburgh 

 University. — Has examined many cases of salmon disease. First heard of it 

 in March 1878 from Carlisle. Dr. Philip Hair sent him part of a salmon. It 

 was a good deal mutilated. Saw it was attacked by fungus. Afterwards 

 received two river trout and one sea trout. Ascertained the fungus to be the 

 Saprolegnia ferax. Had some whole fish sent to him. They were all attacked, 

 and in all parts of the body. The worst injury was generally on the head. Has 

 also had specimens this year from the Eden, Nith, Caldew, and Tweed. The 

 disease was identical in each case. 



[Produces specimen of testicles of a male salmon.] 

 The spermatic ducts are injected with red. It is intended to show the 

 healthiness of the organs in a very diseased salmon. 



[Produces the ova of a female fresh-run fish taken at Berwick.'] 

 The fish was very much diseased, but the ova are healthy. 



[Produces the cloaca of a female salmon to show how the ova escape.'] 

 Much has been said of fish not being able to spawn, owing to detention and 

 being prevented from reaching the beds. When the ova are ripe, and dehiscence 

 takes place, spawning cannot be retarded. The fish has no power to retain 

 the loose ova, even for a short period. The mere motion of swimming would 

 cause the ova to extrude. The abdominal pore is always large, and much 

 larger during spawning. There is no ovi-duct. 



The ova and ovaries produced were taken from a fish sent by Mr. List on 

 11th April. The fish had 24 patches of fungus, some of them 4 inches long, 

 one in the mucous fold of the mouth. The fish could not breathe freely, and 

 would have died from its effects. The whole of the germinal membrane was 

 healthy and full of next year's germs. 



It was an abnormal time for the fish to be gravid. 



Ova ripen at different seasons. The ova are not mature till they are 

 separated. It is remarkable that Mr. List should find 124 female fish in May 

 with the ova ripe. The ova would have run out if dehiscence had taken place. 

 Redisposition of the ova in the ovaries cannot take place. 



The male salmon seeks the eggs, and is content if he gets the eggs and sheds 

 his milt over them to fructify them. There is no sphincter muscle in the 

 abdominal pore of a female salmon. 



The disease cannot have arisen from the retention of ova. Has seen more 

 females than males diseased. They have been clean fish mostly. Has seen 

 spawned fish diseased, both male and female. The fish from the Caldew was 

 spawned. It was killed on the 2nd February 18/9. 



The fungus has been well-known since 1836. Its mode of reproduction's de- 

 scribed by German authors and by Dr. Burden Sanderson. His own observa- 

 tions agree with their descriptions. The fungus is both a-sexual and bi-sexual. 

 First, there are zoospores which are very plentiful, hundreds in a spore case. 

 They are produced in the filaments of the fungus. The zoospore produces 

 a plant which produces another spore called oospore. These are found in a 

 globular cell called ogonium by botanists. These are different from the zoospores. 

 Has only seen four cases in which there were from four to eight spores in each 



