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 your continued only 694 parts of starch and gluten in 1,000 parts, instead of the 995 parts of the nutritious matter which if ought to have contained. In 1806 the quantity was absolutely reduced to 203 parts. In 1810-11-12, when wheat was at its highest price during the war, corn rust was so prevalent and severe, the foliage of the plants so eaten up with it, and in consequence the grain so small and shrivelled, that, much as it was wanted, it was not considered worth while to thrash it out. It has been noticed that severe attacks of corn rust have more than once been coincident with the appearance of cattle plague. The last time that the cattle plague was prevalent in this country the clothes of people walking through corn fields became orange coloured from the dusty spores falling on them.

Smut is individually a very minute fungus, and yet of all the corn parasites it most readily attracts attention. It is a species of Ustilago that attacks the anthers and ovaries of wheat, barley, oats, maize, and rice, plants whose fertility and well-doing are of the utmost importance. It appears as a white viscid fluid, which dries up into a sooty, pulverulent mass. A German some years since attempted to prove that this powder was simply a collection of diseased cells, and therefore not a fungus, but he was easily refuted, for he was shown in the microscope the germinating spores.

Bunt (Tilletia caries) is a concealed foe, its residence is in the growing seed, and it is not till the farmer takes his sample after thrashing that he detects the presence of this pest (the little bunch of pappus at the upper end of the seed is not white, as it ought to be, but dark and dusty.) On careful search he then finds some distorted grains containing a fetid powder, which under a microscope is seen to consist of brown reticulate spores. Of course the presence of much of this fungus would he detected in the flour by its colour and smell, but the millers get rid of the affected grains by rolling and blowing. This fungus has not been destructive for some years.

In northern and cold countries where the soil is poor, rye is almost the only cereal grown. This grain is peculiarly liable to the attack of a fungus called Ergot. It is often present in such large quantity that when ground up and eaten a train of peculiar symptoms is produced, called ergotism, and instances are mentioned in which the continued use of the diseased grain has caused death. The same fungus grows on some of our pasture grasses, and often occasions great mischief to cattle.

In some parts of France the peasantry do not object to eat mouldy bread, and in most instances with impunity; but the species of mould varies. and alarming effects have sometimes followed. These, together with experiments performed on animals, prove that bread in a state of mouldiness will cause death. M. Barral, the French analyst, who reported to his Government on these cases, advises "that as most people are unable to distinguish the species of mould, the use of all bread in such a condition should be avoided."

Next importance to corn as a starch producing vegetable is the potato. Many funguses attack it. The Phytopthera infestans, that is so