I02 THE GOLDFISH AND ITS CULTURE. 



microscojje, reveals a number of parasites darting about hither and 

 thither across the field of the instrument. These minute organic 

 bodies, technically termed baclcrice, resemble a wood-tick in general 

 shape. They appear to eat into the skin of the fish, destroying that 

 structure, and in consequence interfere very much with the function 

 the skin performs in throwing out poisonous substances that form in 

 the tissues inside. The beautiful colors of the fish disappear from 

 the tainted parts, they .becoming quite black. The result of the 

 disease is the death of the fish. 



When afilicted with the trouble, the fish can be observed rubbing 

 itself against the plants, the rocks, or in the sand upon the bottom of 

 the aquarium. 



The cause of the disease may be found in the usual over- feeding, 

 in which case the remnants of food remain in the water until decom- 

 position sets in. The temperature not being favorable for the pro- 

 duction of water-purifying insects, the bacteria; make their appearance 

 greatly to the detriment of the fish*. 



The name "slime" has heretofore been applied to this description 

 of disease, but without. any apparent reference to the cause producing 

 the trouble. In the author's opinion, it is the presence of the para- 

 sites that makes the whole difficulty. They annoy the fish by their 

 presence, their attacks upon its skin setting up an increased flow of 

 blood to the part upon which the thick coat of slime is found. 

 Manifestly the best method of treating the disease is the removal, or 

 rather the prevention, of the cause, for if the bacteria; are not allowed 

 to develop, they of course can do no harm. 



Tadpoles and snails should be put into the aquarium to consume 

 any remaining particles of food, and the feeding itself more carefully 

 attended to. Place the aquarium in a warm and light location, 

 adding to the water a pinch of table-salt when filling the vessel. 



