380 Part III. — Seventh Annual Report 



remains of the empty tubules, however, from the mouth after a period of 

 time, which varied from half-an-hour to three hours. 



I now determined to attempt a renewal of this experiment, but in this 

 ewse to effect a slight abrasion of the epidermal covering and then to 

 apply the fungus by slight rubbing. However, in this experiment, I was 

 fated to have an able assistant in the shape of a pet domestic cat, which 

 overnight amused himself with the fish to such advantage that next 

 morning the gold-fish were almost entirely scaleless, although otherwise 

 they seemed perfectly healthy. I therefore rubbed them all over with 

 the fungus, but as before no result whatever accrued. Various other 

 experiments of the same nature were also attempted, with this difference 

 that abrasion was effected by forcible but gentle removal of scales from 

 the sides of the fish, and now instead of as before keeping up a constant 

 supply of fresh tap water, it was left unchanged in the vessels for periods 

 varying between a day and a week. In these cases, although the water 

 became so filthy as to be quite milky, and large masses of bacteria clung 

 to the sides of the fish, no result followed. In one case, however, one 

 gold-fish died and was left in the water for three days, the others being 

 removed, when it was seen to have a fine growth of the fungus covering- 

 it in twenty-four hours, and which in two days had completely surrounded 

 it, the filaments being on an average about J of an inch in length. 



The other fish, having now been given a plentiful supply of fresh 

 water every two days, seemed to return to their normal state, but six 

 weeks from the time of attempted infection, one minnow was seen to have 

 a slight furry appearance on one side and died within six hours after this 

 observation had been noted. Being now left in the glass vessel with two 

 other minnows, the fungus was seen to form upon it most luxuriantly, and 

 looking very much of the same nature as that which occurred upon the gold- 

 fish. Up to this time I had been working with two glass vessels A and B. 

 In A were the three gold-fishes alone, while in B there were three gold-fish 

 and three minnows. The infected gold-fish died in A, and afterwards, I 

 placed one of the minnows from B into A, and it was this minnow which 

 died, and on which the fungus appeared. So that it might be inferred 

 that the infection had been derived from the gold-fish which had died in 

 A. The dead minnow remained in A twenty-four hours when I determined 

 that I would on the following morning, after the completion of forty-eight 

 hours remove it to B and see if infection of the other two minnows would 

 follow. However, over night a curious incident happened in that a special 

 bacterium had gained access to vessel B, and in the morning the water was 

 quite milky, and in this way contrasted with the clear water in A in which 

 the dead minnow and two gold-fishes were, and which might have been 

 expected to be in a worse state than the others, on account of the presence of 

 the dead minnow. In B the fish were holding to the surface of the water and 

 almost one might think trying to put their heads out of it, and all died in 

 the course of the forenoon with the sole exception of one gold-fish which 

 lived till the evening. The stench emanating from the water in vessel B 

 was so overpowering, that it could be felt throughout the whole house, and 

 I was thus forced to get rid of it. I mention this incident, as it clearly 

 indicates the effect that certain bacteria may exert on fish through the 

 medium of the water. The dead fish have been carefully preserved and I 

 hope later to see whether or not the internal organs have been 

 affected. 



On microscopic examination the fungus affecting the minnow which 

 died presented an altogether different appearance in its method of fructi- 

 fication from that of the ordinary S. ferax got from the salmon and that 

 found on the dead minnow, and agrees somewhat with the form known as 



