Proceedings. 63 



Trout and Charr is a matter of faitli with fishermen, but to 

 instance this as a cause of Saprolegna when it attacks fish 

 quite as freely in summer is absurd. 



To sum up this evening's notice of this most obscure though 

 widely-distributed disease, I will mention as to its cause and 

 remedy the opinions of Mr. Tegetmeier and Mr. Stirling. 

 Mr. Tegetmeier says: — "My belief is that this disease does 

 not break out spontaneously upon all or any fish ; but that 

 in the first instance it invariably attacks fish that are 

 already in bad or lowered health, or are otherwise diseased ; 

 but when it has got ahead it attacks even healthy fish. And 

 this we find to be the course with most diseases that are 

 epidemic." Most of the fish from the Eden were terribly 

 infested with tape and other worms of considerable magnitude, 

 while there were some good fish attacked, which in some sort 

 verifies our assumption. The latter assumption I should be 

 slow to allow, as the difficulty in proving the health of the 

 fish would be insurmountable ; also tape worms do not at all 

 prove fish to be unhealthy, perhaps even the reverse. He 

 proceeds to describe Eoach which he kept in a tank as baits, 

 amongst which the disease often appeared, and says — "Many 

 times have I seen fungoid disease occur to these fish so con- 

 fined, and, what is more remarkable, in almost every case it 

 has been at about the spawning season, the time when it is 

 most active in Salmon. In my experience it appears at all 

 seasons, though I should readily allow that the spawning 

 season would be most suitable, as the fish would be more 

 susceptible of changed conditions." But on this point we 

 may ask why it should chiefly attack the male Salmon, as it 

 undoubtedly does. Is it sent to clear away the useless 

 superfluity of males, as the bees kill the drones and the 

 female spider kills the male ; and are the males for that 

 reason more prone to attack ? The observations of Mr. 

 Blackwell (of the Conway) may throw some light upon this 

 point, for he wrote a paper on the subject, and told me 

 personally that he had examined the stomachs of hundreds 

 of Salmon and always found them quite empty. He said he 

 was convinced that they never ate anything during their stay 



