THALLOGEX^. 721 



uterine contractious in labour, and for other purposes, is now 

 proved to be the sclerotiiun (compact mycelium or spawn) of 

 Clavkeps purpurea. "WTieat and a number of other grasses are 

 also frequently ergotised. 



Fungi are often very destructive to living plants and animals, 

 by growing upon them. Thus, in plants, the diseases known 

 as blight, mildew, rust, smut, vine-mildew, potato-disease, ergot, 

 &c., are either caused from, or accelerated by, the agency of 

 fungi. Many valuable communications attempting to prove that 

 fungi are either the cause of or the means of propagating 

 various diseases in the human subject have been also made 

 during the last few years, and there can be no doubt but that 

 fungi are associated with several cutaneous and other diseases 

 to which the human body is liable. This subject is still 

 under investigation by acute and discriminating observers, and 

 promises to throw much light on our knowledge of the cause 

 and propagation of diseases ; it is one replete with interest, but 

 which cannot be entertained further in this volume. The disease in 

 the silkworm, known under the name of muscca-dine, is produced 

 by one or more species of Botrytis. Similar diseases also occur 

 in other animals. Caterpillars are frequently attacked by 

 species of Spharia or CJavic^ps, in China, Australia, Xew Zea- 

 land, &c., and ultimately destroyed. The mucous membrane of 

 birds, &c., is also commonly infested with fungi of various kinds. 

 The disease called Dry Eot, which occurs in wood, is especially 

 caused by dampness, and the subsequent development of the 

 spores of fungi, as those of Merulius lacryrnans and J/, vastator, 

 and Polyporus destructor, ^-c. The different kinds of Moulds which 

 are found on bread, cheese, preserves, fruits, paper, books, &c., 

 are fungi of the species 3Iucor, Botrytis, Aspergillus, Penicillium, 

 Oidium, &c. The following fungi require a more detailed 

 notice : — 



Agaricus. — Agaricus (PsaUioia) campestris, the Common iTushroom, and 

 its varieties ; A. at'vensis (Fsalliota), A. {Marasmius) oreades, the Champig- 

 non, A. deliciosus, A. ccesareus, and A. (Lejnota) procents, dr., are largely used 

 for food in this and other parts of the world. (See Properties and Uses of 

 Fungi.) The subterranean mycelium of various species of Agaricus. as that of 

 A . oreades. A.prunu I us, A . Orcella , A . ca mpestris, dx. , and that of allied genera, 

 developes in a radiating manner, and, by the remains acting subsequently as 

 a manure, causes the grass in our meadows, in such places, to grow in a very 

 Itixuriant manner in rings, which are commonly called fairy rings. 



Amanita (Agaricus) muscaria is a very poisonous species. It possesses 

 narcotic and intoxicating properties, and is much used in Kamtschatka, 

 and some other parts of the Russian empire, as a narcotic and intoxicating 

 asent. It possesses the remarkable property of imparting its intoxicating 

 effects to the fluid excretions of those who partake of them. This fungus, 

 when steeped in milk, &c., acts as a poison to flies ; hence its specific name. 



Boletus edulis and several other species are edible. B. edulis is much es- 

 teemed in Italy, &c. 



Claviceps iCo?-diceps or Sphceria).— The disease called Ergot, which occurs 



in the grains of Rye and other grasses, is produced by C. purpurea. (See 



Properties and Uses of Fungi.) C. Robertsii, C. sinensis, C. entomorrhiza, 



and other species, frequently attack caterpillars in a living state, which they 



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