AILMENTS AND DISEASES 



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FIG. loi. Lymphosporidium truttes^ a 



Bacterian parasite, i. Enlargement. 



2. Greatly enlarged Blood corpuscles 



and Bacteria. 



diseases of fishes. They have not received much attention from Bacteri- 

 ologists and but few have been identified. 



Lymphosporidium truttie produces a dis- 

 ease in aquaria and among domesticated 

 fishes not yet observed in wild ones from 

 natural waters. The bacteria, Fig. loi, are 

 short rodlike micrococci which grow out into 

 filaments, and infest the gills, blood, muscles, 

 skin and surface generally. This micrococcus 

 Is usually present in cases of Autotoxine of 

 aquarium fishes. Healthy fishes succumb 

 to the bacteria in a few days when inoculated beneath the skin and after a 

 longer time by mixing cultures with their food. It is to be hoped that 

 future investigations will familiarize the fish-culturlst with many other of 

 these bacterial causes of fish diseases, and with methods for their destruc- 

 tion. 



Sporozoa. This section of the Protozoa includes orders which 

 contain many parasitic genera. The orders of the Cytosporidia are the 

 Gregarinida, Coccidiida, Hamosporidiida and Gymnosporidiida. The orders 

 of Myxosporidia are the Phanocystida and Microsporidiida; and in addition 

 to these are the orders Sarcosporidia, Amcebosporidia and Serumsporidia. 



Gregarinida. Of this order none of the genera have been found 

 as parasites on freshwater fishes or amphibia. 



Coccidiida. The freshwater parasites of this order belong to the 

 genera Rhabdospora and Coccidium. R. thelohani have been found in the 

 intestines of the perch, the ovarian tissues of the pike-perch, and in the 

 liver of the stickleback; C. metshinkovi in the intestines of the goby; and 

 C. gasterostei in the liver of the stickleback. None have been found on 

 the Cyprinidse. 



fig. J02. Myxobolus sp. incert^ a Sporo- 

 zoan parasite of the Goldfish and other Cyprinidae. 

 Greatly enlarged. 



1. Cyst in cuticle and tissues. 



2. Cyst containing vacuoles. 



3. Ruptured cyst and escaping vacuoles. 



FIG. I02A. Head and shoulder of a Goldfish 

 affected withMyxohoius sp. inctrt. 



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