182 



;tppeainiK'e of that in the pond before July -ird, and it 

 smelled offensively. The water was run off several times, 

 and on each occasion dead and dyinjs^ fish were found. 

 Slig-ht infection of the liver was observed in several 

 during the early part of the time, but it was less and less 

 obvious as time went on. I find that 17 died during 

 that period. After the fish Avere returned to the pond, 

 three were found dead on August 14th and the liver of 

 one of them Mas foujid to be slightly infected. The 

 second had a dozen worms,* of the same species as those 

 I sent you some time ago, coiled up in a mass in the 

 liver, which was highly congested, while the liver of 

 the third appeared to be quite healthy. Another fish 

 was found dead on August 21st, with the liver very badly 

 infested. On September 20th the bottom of the pond 

 was again examined, and nine dead and 14 sick fish were 

 found. On this occasion no trace of the parasite was 

 seen, but every fish had the open sores on the top of the 

 head, and at the base of the tail on the unpigmented side. 

 The one I sent to you on October 10th was one of 17 

 sickly ones found that day, but all the viscera of six, 

 taken at random, appeared to be perfectly healthy. 

 Every one had the external abrasions." 



To the naked eye a portion of infected liver or 

 kidney appears to contain small white globular bodies 

 varying in size from 0'2-3 to 1 mm. In some cases, these 

 arc very sparsely scattered through the tissue, but in 

 otho]- specimens they are densely crowded together, and 

 seem to hang together. Fig. 3, pi. XVI., represents a 

 section through one of these masses. It M'ill be seen that 

 we have not to do here with a cyst, but simply with the 

 mycelium and conidiophores of a fungus, the whole 



'■= Nematode woims, with some plerocercoid larvse of the cestode 

 Tchrn-hynchii^ erimirnis. van Brnedeii. 



