
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 <chlya 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 4. megosperma, 
A. americana, A. oblongata and A. racemosa. 
ApHanomyces. This fungus is parasitic on the Alge, 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 
hyphe, forming a fine film over the plant, which it destroys. The sporangia 
usually have a prickly appearance. The more common species are 
A phonomyces levis, A. phycophilus and A. scaber. 
Leprometus. 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 
hyphe. 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 Leptometez 
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 alge, and in the 
slime of stagnant water. ‘There are no reported instances of their having 
become parasitic on fishes but always indicate stream pollution. 
ApopacHLya. 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, 4podachlya brachynema, A. pyrifera and A. completa. 
As they are harmless to fishes they need no further description here. 
OrHER Common Forms oF Funct. 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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