. Minnesota plant diseases. Plant diseases. 72 ^. Fig. 33.—A spore-case mold showing escaping swim- ming spores; each of the spores is provided with two swimming lashes which whip about in the wa'.er and propel the soores. Highly magnified. After Zopf. Minnesota Plant Diseases. attack healthy fish unless perhaps through the respiratory system, but succeed if the fish are in some way in- jured, for instance at points where the scales have been rubbed off. When once the parasites are estabHshed they gradually spread over the body of the fish and ultimately cause its death. The fungus produces an
. Minnesota plant diseases. Plant diseases. 72 ^. Fig. 33.—A spore-case mold showing escaping swim- ming spores; each of the spores is provided with two swimming lashes which whip about in the wa'.er and propel the soores. Highly magnified. After Zopf. Minnesota Plant Diseases. attack healthy fish unless perhaps through the respiratory system, but succeed if the fish are in some way in- jured, for instance at points where the scales have been rubbed off. When once the parasites are estabHshed they gradually spread over the body of the fish and ultimately cause its death. The fungus produces an enormous number of spores which are for the most part furnished with whip-like lashes for propelling purposes. Oc- casionally these fish molds cause epi- demics and vast numbers of fishes may then succumb. The occurrence of several such epidemics is known. These fungi are very often the cause of the death of fish in aquaria such as common gold fish. The danger from such fungi can be lessened by keeping the aquaria scrupulously clean so as to furnish little chance for the sapro- phytic existence of the fungus. The infected fish should be removed as soon as possible to prevent the forma- tion of more spores. The injuries of these fungi are not confined to the fish in lakes and streams but are sometimes a cause of great loss in the fish hatcheries where the eggs may be attacked. Some of the bread mold aUies are also known as inhabitors of fish eggs. On the Amphibia, the frogs and their relatives, few fungi have been found. In this state mud puppies have been observed, which have been killed by certain fish molds. The fungus appeared on an apparent- ly healthy mud puppy as a thin filmy spot which rapidly grew larger, coa- lescing with other spots until the ani-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectplantdi, bookyear1905
