
AILMENTS AND DISEASES 

Funcus on Spawn. The spawn of fishes is attacked by a fungus 
which eaten itself by short hairlike growths on the surface. Fig. 75. It 
is usually one of the species of the Saproleg- 
niacee, Saprolegnia ferax or Dictyuchus polyspo- 
* rus, the spores of which are present in all natu- 
ral waters,and are more fully described hereafter. 
TreaTMENT. There is little to be done 
for this diseased condition other than to pick 
out the affected eggs with tweezers. Eventhen 
more fertile eggs may be injured than would be 
saved. Under good conditions only the un- 
fertile opaque eggs are attacked; and if the 
parents are healthy and the water conditions 

good, these are not likely to be present in sufh- 
Fig. 75. Funguson Spawn, 
Naprolipnia, forces cient number to warrant the removal of the 
pe ccadly calateed affected spawn. If the fishes are weak or over- 
spawned, at times nearly all the eggs are unfertile or the fry hatches weak, 
and on such occasions all the eggs and fry may be attacked by the fungus. 
When ina day or two the spawn shows a majority of affected eggs, it 1s 
best to destroy both it and the spawning plants, to prevent a further 
spread of the fungus and the diseased condition. 
It is probably always best to take the spawn and the plants to which 
it adheres from the spawning bed and place them in filtered water to hatch, 
thus largely avoiding the danger of the presence of fungus spores and 
those of parasites; but a few pots of growing plants should be introduced 
to supply the necessary oxygen and to prevent the asphyxiation of the 
fry. A small dish containing clean soil should also be furnished as it con- 
tains substances necessary for nutrition and will stimulate the development 
of minute plant andanimal life, the first food of the young fry. The presence 
of these low forms is manifested by the greenish color of the water. 
After the fry are a week old, a half pint of water of pronouncedly green 
color should be added every few days, and then live food should be fed. 
Wuire Funcus. One of the most frequent diseases of the goldfish 
and other aquarium fishes is manifested by the appearance of a white coating 
on the tail and fins which spreads to the body, operculz and into the gills 
of the fish, destroying the fins, covering the body with a threadlike scum and 
finally causing the death of the fish from exhaustion, asphyxiation and inter- 
ference with the proper functions of the skin by obstruction of the surface 
pores and the induced inflammation. Figure 76. 
The disease is most often introduced into the aquarium by newly ac- 
quired fishes that may have been shipped long distances in cans containing 
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