AILMENTS AND DISEASES 



The large group of Schizomycetes or Yeast fungi are not treated of 

 here as they do not enter into the subject. 



Treatment for Vegetal Parasites. Fishes affected with parasitic 

 fungi may be successfully treated and cures effected. When given imme- 

 diate attention, the spread of the fungi may be checked by salt baths or local 

 application of strong brine, followed by the peroxide treatment; but when 

 the ravages are not at once checked they produce fatal results. They 

 sometimes produce epidemics which cause the deaths of thousands of food 

 fishes and of entire broods of goldfishes. There is no radical fungicide 

 which is invariably effective with the fungi. The remedies for animal par- 

 asites should be applied as usually, a microscope examination only can 

 determine what form of parasite is present. 



Prevention of Fungi in Aquaria. Filtration of the water is a 

 radical prevention of the introduction of and the removal of Fungi in the 

 aquarium; but the spores may be brought over into the filtered water by 

 the fishes themselves or on aquatic plants, snails and tadpoles, when 

 these are introduced in fungused condition, or together with live food 

 taken from unsanitary localities. Cleanliness in every particular is the 

 best preventive, together with a frequent careful inspection of both the 

 fishes and the scavengers, and the isolation of any which may have a 

 doubtful appearance. Prevention is always easier than a cure. Strong and 

 healthy fishes are seldom attacked by vegetal parasites, but the disease is 

 sometimes communicated from weakened or bruised fishes introduced into 

 a previously sanitary and well-established aquarium. 



AlgvE More or Less Parasitic. The common forms of Algae 

 which adhere to the aquarium, on the aquatic plants, or suspended in the 

 water, belong to a number of genera. Those most frequently met with 

 are the following: 



Chlorophyllace^. In the clouded water of a stagnant aquarium 

 two forms of Chlorococcum, one motile and the other at rest, were found 

 by Dr. H. C. Wood; the younger forms green, the older ones darkish- 

 brown in color. They were so numerous as to make the water opaque and 

 stagnant. 



Androgynia huntii, forms delicate bright-green fringes on the plants 

 and glass of the aquarium. 



Bulbochata dumosa, forms small bushy growths on larger Algae, Con- 

 fervae and other plants in the aquarium. 



Tolypothrix distorta, forms microscopic bright-green tufts or balls 

 adhering to plants in the aquarium and to the glass. 



Mastigonema elongatum, forms blackish-green nodules about the size 

 of a pin head on Brook-moss and Characeas. 



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