Fungi: Their Nature and Uses

by M. C. Cooke

The Tuberacei[D] are remarkable amongst the fungi in being all of them more or less hypogeous. They are natives of warm countries, and are distributed into numerous genera and species. The Tuberacei constitute in Northern latitudes a group of fungi very poor in specific forms. The few species of the Hymenogastres belonging to Sweden, with the exception of Hyperrhiza variegata and one example of the genus Octaviana, are confined to the southern provinces. The greater part of this group, like the Lycoperdacei, are met with in the temperate zone. Most examples of the genus Lycoperdon are cosmopolitan.

The Nidulariacei and the Trichodermacei appear to be scattered over the globe in a uniform manner, although their species are not everywhere similar. The same statement applies to the Myxogastres, which are common in Lapland, and appear to have their central point of distribution in the countries within the temperate zone. At the same time, they are not wanting in tropical regions, notwithstanding that the intensity of heat, by drying up the mucilage which serves as the medium for the development of their spores, is opposed to their development.[E]

Of the Coniomycetes, the parasitic species, as the Cæomacei, the Pucciniei, and the Ustilagines, accompany their foster-plants into almost all regions where they are found; so that smut, rust, and mildew are as common on wheat and barley in the Himalayas and in New Zealand as in Europe and America. Ravenelia and Cronartium only occur in the warmer parts of the temperate zone, whilst Sartvellia is confined to Surinam. Species of Podisoma and Rœstelia are as common in the United States as in Europe, and the latter appears also at the Cape and Ceylon. Wherever species of Sphæria occur there the Sphæronemei are found, but they do not appear, according to our present knowledge, to be so plentiful in tropical as in temperate countries. The Torulacei and its allies are widely diffused, and probably occur to a considerable extent in tropical countries.

Hyphomycetes are widely diffused; some species are peculiarly cosmopolitan, and all seem to be less influenced by climatic conditions than the more fleshy fungi. The Sepedoniei are represented by at least one species wherever Boletus is found. The Mucedines occur everywhere in temperate and tropical regions, Penicillium and Aspergillus flourishing as much in the latter as in the former. Botrytis and Peronospora are almost as widely diffused and as destructive in warmer as in temperate countries, and although from difficulty in preservation the moulds are seldom represented to any extent in collections, yet indications of their presence constantly occur in connection with other forms, to such an extent as to warrant the conclusion that they are far from uncommon. The Dematiei are probably equally as widely diffused. Species of Helminthosporium, Cladosporium, and Macrosporium seem to be as common in tropical as temperate climes. The distribution of these fungi is imperfectly known, except in Europe and North America, but their occurrence in Ceylon, Cuba, India, and Australasia indicated a cosmopolitan range. Cladosporium herbarum would seem to occur everywhere. The Stilbacei and Isariacei are not less widely diffused, although as yet apparently limited in species. Isaria occurs on insects in Brazil as in North America, and species of Stilbum and Isaria are by no means rare in Ceylon.

The Physomycetes have representatives in the tropics, species of Mucor occurring in Cuba, Brazil, and the southern states of North America, with the same and allied genera in Ceylon. Antennaria and Pisomyxa seem to reach their highest development in hot countries.

The Ascomycetes are represented everywhere, and although certain groups are more tropical than others, they are represented in all collections. The fleshy forms are most prolific in temperate countries, and only a few species of Peziza affect the tropics, yet in elevated districts of hot countries, such as the Himalayas of India, Peziza, Morchella, and Geoglossum are found. Two or three species of Morchella are found in Kashmir, and at least one or two in Java, where they are used as food. The genus Cyttaria is confined to the southern parts of South America and Tasmania. The United States equal if they do not exceed European states in the number of species of the Discomycetes. The Phacidiacei are not confined to temperate regions, but are more rare elsewhere. Cordierites and Acroseyphus (?) are tropical genera, the former extending upwards far into the temperate zone, as Hysterium and Rhytisma descend into the tropics. Amongst the Sphæriacei, Xylaria and Hypoxylon are well represented in the tropics, such species as Xylaria hypoxylon and Xylaria corniformis being widely diffused. In West Africa an American species of Hypoxylon is amongst the very few specimens that have ever reached us from the Congo, whilst H. concentricum and Ustulina vulgaris seem to be almost cosmopolitan. Torrubia and Nectria extend into the tropics, but are more plentiful in temperate and sub-tropical countries. Dothidea is well represented in the tropics, whilst of the species of Sphæria proper, only the more prominent have probably been secured by collectors; hence the Superficiales section is better represented than the Obtectæ, and the tropical representatives of foliicolous species are but few. Asterina, Micropeltis, and Pemphidium are more sub-tropical than temperate forms. The Perisporiacei are represented almost everywhere; although species of Erysiphe are confined to temperate regions, the genus Meliola occupies its place in warmer climes. Finally, the Tuberacei, which are subterranean in their habits, are limited in distribution, being confined to the temperate zone, never extending far into the cold, and but poorly represented out of Europe. One species of Mylitta occurs in Australia, another in China, and another in the Neilgherries of India; the genus Paurocotylis is found in New Zealand and Ceylon. It is said that a species of Tuber is found in Himalayan regions, but in the United States, as well as in Northern Europe, the Tuberacei are rare.

The imperfect condition of our information concerning very many countries, even of those partially explored, must render any estimate or comparison of the floras of those countries most fragmentary and imperfect. Recently, the mycology of our own islands has been more closely investigated, and the result of many years’ application on the part of a few individuals has appeared in a record of some 2,809 species,[F] to which subsequent additions have been made, to an extent of probably not much less than 200 species,[G] which would bring the total to about 3,000 species. The result is that no material difference exists between our flora and that of Northern France, Belgium, and Scandinavia, except that in the latter there are a larger number of Hymenomycetal forms. The latest estimates of the flora of Scandinavia are contained in the works of the illustrious Fries,[H] but these are not sufficiently recent, except so far as regards the Hymenomycetes, for comparison of numbers with British species.

The flora of Belgium has its most recent exponent in the posthumous work of Jean Kickx; but the 1,370 species enumerated by him can hardly be supposed to represent the whole of the fungi of Belgium, for in such case it would be less than half the number found in the British Islands, although the majority of genera and species are the same.[I]

For the North of France no one could have furnished a more complete list, especially of the microscopic forms, than M. Desmazières, but we are left to rely solely upon his papers in “Annales des Sc. Nat.” and his published specimens, which, though by no means representative of the fleshy fungi, are doubtless tolerably exhaustive of the minute species. From what we know of French Hymenomycetes, their number and variety appear to be much below those of Great Britain.[J]

The mycologic flora of Switzerland has been very well investigated, although requiring revision. Less attention having been given to the minute forms, and more to the Hymenomycetes than in France and Belgium, may in part account for the larger proportion of the latter in the Swiss flora.[K]