AILMENTS AND DISEASES 



migrations. The entire body becomes covered with white gnawing ulcers, 

 the gills livid, the eyes coated and glazed, and the surface ulcerated so 

 that the raw flesh may be seen. When the fungus reaches into the 

 respiratory organs death results. This fungus may be recognized under 

 the microscope by its stiff and bristly appearance. The most common 

 species of this genus is Achlya apiculata, a minute vegitative body 

 having short, stout and stiff hyphae and abundant sporangia upon short 

 branches. It occurs on dead leaves and similar substances in Stillwater 

 pools and ditches, in the slime of stagnant water and in rivers and other 

 natural water courses. Other frequently occurring forms are A. megosperma, 

 A. americana, A. oblongata and A. racemosa. 



Aphanomyces. This fungus is parasitic on the Algae, principally on 

 the species Spirogyra and Zygnema, also on some of the Mosses and other 

 low forms of . aquatic plant life. It consists of very slender and delicate 

 hyphae, forming a fine film over the plant, which it destroys. The sporangia 

 usually have a prickly appearance. The more common species are 

 Aphonomyces lavis, A. phycophilus and A. scaler. 



Leptometus. This fungus grows in water containing considerable 

 organic impurities especially in that to which the waste of factories finds 

 its way. It may be recognized by the many-branching form of the 

 hyphae. The more common species of this genus is Leptometus lacteus 

 a minute felted vegitative body which covers the bottom of streams for con- 

 siderable distances with a thick white layer. Some of the Leptometese 

 also occur abundantly in localities where the streams contain starchy refuse 

 and much decaying vegetal matter. They also flourish on animal remains 

 and slaughter house refuse in streams, on decaying algae, and in the 

 slime of stagnant water. There are no reported instances of their having 

 become parasitic on fishes but always indicate stream pollution. 



Apodachlya. This fungus occurs most frequently upon dead animal 

 matter in water and no certain conclusions have been reached of its 

 becoming parasitic on living organisms. It has received some attention 

 from investigators as it is considered to be the first instance of the 

 occurrence of sexual organs in these low forms of plants. Three species 

 have been established, Apodachlya brachynema, A. pyrifera and A. completa. 

 As they are harmless to fishes they need no further description here. 



Other Common Forms of Fungi. Penicillium, Aspergillus and 

 Mucor are also saprophytes which live upon decaying organic matter and 

 particularly flourish in water containing salts of ammonia. The common 

 forms are Penicillium glaucum, Eurotium aspergillus glaucus, Mucor mucedo, 

 M. racemosus and M. circinelloides. 



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