ECONOMIC MYCOLOGY. 235 



year oontaiued only 601 parts of starch and gluten in 1,000 parts, instead 

 of the 995 parts of the nutritions niuttor which it ouglit to have 

 contained. In 1800 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 fohage 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 com 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 faUing on them. 



Smut is individually a very minute fungus, and yet of all the com 

 parasites it most readily attracts attention. It is a species of Ustilago 

 that attacks the anthers and ovaries of wheat, barlej', oats, maize, and 

 rice, plants whose fertiUty and well-doing are of the utmost importance. 

 It appears as a white viscid fluid, which dries up into a sooty, pulveru- 

 lent 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 tcatid powder, which under a microscope is seen to consist 

 of brown reticulate spores. Of course the presence of much of this 

 fungus would be detected in the flour by its colour and smell, but tho 

 millers got rid of the affected grains by rolUng and blowing. This 

 fungus has not been destructive for some years. 



In northern and cold countries where the soil is poor, ryo is almost 

 the only cereal grown. This grain is pe^^uliarly 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 pastiu'e 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 

 mouldiuess will cause death. M. Barrul, the French analyst, who 

 reported to his Government on these cases, advises " that as most 

 people arc unable to distinguish the species of mould, tho use of all 

 bread in such a condition should be avoided." 



Next in importance to corn as a starch producing vegetable is the 

 imtato. Many funguses attack it. The Peronospora infcstana, that in ho 



