27 



disease, and they lived for . some time afterwards ; so that 

 this fungus was quite destroyed by the administration of 

 this bath of salt water. Of course these fish were put under 

 the doctor directly there was the slightest sign of this dan- 

 gerous disease upon them, and since then they had hardly 

 ever lost a fish. The black bass also which came over from 

 America in the fresh-water tanks became very seedy, and he 

 thought that they should lose a great many, but he got some 

 salt water out of the sea, kept them in it two days, and they 

 all recovered and were doing well wherever they had been 

 sent. 



Sir JAMES MAITLAND seconded the motion. He had 

 hoped that Professor Huxley would have gone very widely 

 into the question of the diseases of fish, for they were by 

 no means confined to the Saprolegnia ferax. Although 

 perhaps of late it had occupied a large portion of the sci- 

 entific research which had been bestowed on the Salmonidae, 

 it must be remembered that in old days when they had not 

 the same restriction and protection they had now, although 

 the disease was occasionally mentioned in books as the 

 murrain among salmon, it was uncertain how far it extended. 

 In those days the waters were frequented by otters, and 

 there was a good deal of poaching, and he doubted if many 

 fish that got high up the rivers ever returned into the sea, 

 and that might account for the contradictory results ob- 

 tained on the Tweed, which showed that exactly four years 

 after the disease broke out in a virulent form the number of 

 fish caught was much larger than before. It might be that 

 the death of those old fish, which in descending the rivers 

 would probably swallow a number of smolts, enabled the 

 river to recoup itself by the growth of the young fish ; and 

 in the case of a shorter river the results might be different 

 In the Tweed there was a long stretch of dead water 



