ECONOMIC MYCOLOGY, 237 



Parasitical fungi, not content with damaging com and potatos, are 

 also very injurious to garden produce ; cabbages, beans, peas, celery, and 

 onions, each of them cherisli and foster some unbidden visitor ; fruit 

 trees, as pears, plums, peaches, filberts, and walnuts furnish a residence 

 for some unwelcome intruder. 



Flowering plants, grown for their beauty, are much injured, and 

 sometimes killed, by parasitical funguses; witness the rose trees and 

 hollyhocks. Two years out of three hopyards are rendered unproductive 

 by attacks of an Erysiphe. 



Timber trees do not suffer much while in growth, yet it is curious to 

 number the varieties of fungus found on them. M. Wessendorf says 

 that " seventy-four attack the lime, of which eleven reside on the leaf ; 

 114 the spruce fir, and no less than 200 the oak ;" among the latter are 

 reckoned those funguses whose ravages in timber-built ships have 

 occasioned a loss in fourteen years estimated at twenty miUions, and 

 which in church and domestic architecture produce great annoyance and 

 expense by causing dry rot. MeruJms lacrymans, Pohjpom.g hybridus, 

 and a Thclephora are the funguses which prey on sound timber ; their 

 mycelium creeps between the cells, and decomposes the lignin and 

 cellulose ; the Merulius has a rusty-coloured irregidar stemless pileus, 

 from whose gills a liquid constantly exudes. 



If the useful plants of other countries are examined, we find in the 

 south of Europe olives, oranges, and onions damaged by a fungus that 

 envelopes their leaves in a covering of soot ; in the Atlantic isles and 

 France the O'idium Tuckeri destroys the grape vine. This fungus first 

 appeared in an English hothouse, and thence has spread in all directions. 

 Our friend, M. Comu, told us last October that another fungus had lately 

 appeared on the vine at Narbonne, causing a disease called Anthracnose. 

 In some parts of Italy the cultivation of the silkworm has been 

 suspended because it is attacked and destroyed wholesale by a species of 

 mould somewhat resembling that which kills flies in the autumn, and 

 leaves them adhering to the glass in our \vindows, surrounded by a cloud 

 of wliite spores. In America the maize is often much injured by a smut 

 that causes large and curious distortions of the grain and cobs. The 

 plant which of all others is the most important for clothing purposes — 

 the cotton plant — has two formidable enemies. One attacks the leaves, 

 the other the pods. 



Some manufactures are much impeded by the growth of moulds. 

 Bleaching cannot be carried on in the fields on account of moulds gi'owing 

 and causing unsightly and in-emovable blotches on the fabric. The 

 preparation of gelatine, maccaroni, hme juice, and wines requires precau- 

 tions to be taken to prevent access of air containing spores of funguses. 

 It would not be difficult to extend the hst of noxious funguses, but enough 

 has been said to show that man's person, food, clothing, building 

 materials, and occupations are all injured by divers species of fungus. In 

 proportion to the amount of injury they cause, they become important. 

 It must be desirable, therefore, that their structure, habits, and life- 

 histoi-y should be carefully studied, so that advantage may be taken of 

 every opportunity of lessening or preventing their iujiuious effects. 



