Chapter 26
The genera _Lentinus_ and _Lenzites_ are found in every region of the world; their principal centre, however, is in hot countries, where they attain a splendid development. On the contrary, towards the north they rapidly decrease in number.
The _Polypori_ constitute a group which, unlike that of the Agarics, especially belongs to hot countries. The _Boleti_ constitute the only exception to this rule, since they select the temperate and frigid zones for their special abode, and some of them at times find their way to the higher regions of the Alps. No one can describe the luxuriance of the torrid zone in _Polypori_ and _Trametes_, genera of _Hymenomycetes_, which flourish beneath the shade of the virgin forests, where perpetual moisture and heat promote their vegetation and give rise to an infinite variety of forms. But though the genus _Polyporus_, which rivals _Agaricus_ in the number of its species, inhabits, in preference, warm climates at large, it nevertheless exhibits species peculiar to each country. This arises from the circumstance that the _Polypori_, for the most part, live upon trees, and are dependent on this or that particular tree for a suitable habitat; and the tropical flora being prolific in trees of all kinds, a multitude of the most varied forms of these fungi is a necessary consequence. _Hexagona_, _Favolus_, and _Laschia_ are common in inter-tropical countries, but they are either entirely absent or extremely rare in temperate climes.
When the majority of the species of a genus are of a fleshy consistence, it may generally be concluded that that genus belongs to a Northern region, even if it should have some representatives in lands which enjoy more sunshine. Thus the _Hydna_ are the principal ornaments of Northern forests, where they attain so luxuriant a growth and beauty that every other country must yield the palm to Sweden in respect to them. In an allied genus, that of _Irpex_, the texture assumes a coriaceous consistence, and we find its species to be more especially inhabitants of warm climates.
Most of the genera of _Auricularini_ are cosmopolitan, and the same is true of some species of _Stereum_, of _Corticium_, etc., which are met with in countries of the most different geographical position. In tropical countries, these genera of fungi assume the most curious and luxuriant forms. The single and not considerable genus _Cyphella_ appears to be pretty uniformly distributed over the globe. The _Clavariæi_ are equally universal in their diffusion, although more plentiful in the north; however, the genus _Pterula_ possesses several exotic forms, though in Europe it has but two representative species. That beautiful genus of _Hymenomycetes_, _Sparassis_, occupies a similar place next the _Clavariæi_, and is peculiarly a production of the temperate zone and of the coniferous region.
The fungi which constitute the family of _Tremellini_ prevail in Europe, Asia, and North America, and exhibit no marked differences amongst themselves, notwithstanding the distances of the several countries apart. It must, however, be stated that the _Hirneolæ_ for the most part inhabit the tropics.
We come now to the _Gasteromycetes_--an interesting family, which exhibits several ramifications or particular series of developments. The most perfect _Gasteromycetes_ almost exclusively belong to the warmer division of the temperate, and to the tropical zone, where their vegetation is the most luxuriant. Of late the catalogue of these fungi has been greatly enriched by the addition of numerous genera and species, proper to hot countries, previously unknown. Not uncommonly, the exotic floras differ from ours, not merely in respect of the species, but also of the genera of _Gasteromycetes_. It must, besides, be observed that this family is rich in well-defined genera, though very poor in distinct specific forms. Among the genera found in Europe, many are cosmopolitan.
The _Phalloidei_ present themselves in the torrid zone under the most varied form and colouring, and comprise many genera rich in species. In Europe their number is very restricted. As we advance northward they decrease rapidly, so that the central districts of Sweden possess only a single species, the _Phallus impudicus_, and even this solitary representative of the family is very scarce. In Scania, the most southern province of Sweden, there is likewise but one genus and one species belonging to it, viz., the _Mutinus caninus_. Among other members of the _Phalloidei_, may be further mentioned the _Lysurus_ of China, the _Aseröe_ of Van Diemen's Land, and the _Clathrus_, one species of which, _C. cancellatus_, has a very wide geographical range; for instance, it is found in the south of Europe, in Germany, and in America; it occurs also in the south of England and the Isle of Wight; whereas the other species of this genus have a very limited distribution.
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 _Roestelia_ 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]
In Spain and Portugal scarce anything has been done; the small collection made by Welwitsch can in no way be supposed to represent the Peninsula.
The fungi of Italy[L] include some species peculiar to the Peninsula. The _Tuberacei_ are well represented, and although the _Hymenomycetes_ do not equal in number those of Britain or Scandinavia, a good proportion is maintained.
Bavaria and Austria (including Hungary, and the Tyrol) are being more thoroughly investigated than hitherto, but the works of Schæffer, Tratinnick, Corda, and Krombholz have made us acquainted with the general features of their mycology,[M] to which more recent lists and catalogues have contributed.[N] The publication of dried specimens has of late years greatly facilitated acquaintance with the fungi of different countries in Europe, and those issued by Baron Thümen from Austria do not differ materially from those of Northern Germany, although Dr. Rehm has made us acquainted with some new and interesting forms from Bavaria.[O]
Russia is to a large extent unknown, except in its northern borders.[P] Karsten has investigated the fungi of Finland,[Q] and added considerably to the number of _Discomycetes_, for which the climate seems to be favourable; but, as a whole, it may be concluded that Western and Northern Europe are much better explored than the Eastern and South-Eastern, to which we might add the South, if Italy be excepted.
We have only to add, for Europe, that different portions of the German empire have been well worked, from the period of Wallroth to the present.[R] Recently, the valley of the Rhine has been exhaustively examined by Fuckel;[S] but both Germany and France suffered checks during the late war which made their mark on the records of science not so speedily to be effaced. Denmark, with its splendid Flora Danica still in progress, more than a century after its commencement,[T] has a mycologic flora very like to that of Scandinavia, which is as well known.
If we pass from Europe to North America, we find there a mycologic flora greatly resembling that of Europe, and although Canada and the extreme North is little known, some parts of the United States have been investigated. Schweinitz[U] first made known to any extent the riches of this country, especially Carolina, and in this state the late Dr. Curtis and H. W. Ravenel continued their labours. With the exception of Lea's collections in Cincinnati, Wright's in Texas, and some contributions from Ohio, Alabama, Massachusetts, and New York, a great portion of this vast country is mycologically unknown. It is remarkably rich in fleshy fungi, not only in _Agaricini_, but also in _Discomycetes_, containing a large number of European forms, mostly European genera, with many species at present peculiar to itself. Tropical forms extend upwards into the Southern States.
The islands of the West Indies have been more or less examined, but none so thoroughly as Cuba, at first by Ramon de la Sagra, and afterwards by Wright.[V] The three principal genera of _Hymenomycetes_ represented are _Agaricus_, _Marasmius_, and _Polyporus_, represented severally by 82, 51, and 120 species, amounting to more than half the entire number. Of the 490 species, about 57 per cent. are peculiar to the island; 13 per cent. are widely dispersed species; 12 per cent. are common to the island and Central America, together with the warmer parts of South America and Mexico; 3 per cent. are common to it with the United States, especially the Southern; while 13 per cent. are European species, including, however, 13 which may be considered as cosmopolitan. Some common tropical species do not occur, and, on the whole, the general character seems sub-tropical rather than tropical. Many of the species are decidedly those of temperate regions, or at least nearly allied. Perhaps the most interesting species are those which occur in the genera _Craterellus_ and _Laschia_, the latter genus, especially, yielding several new forms. The fact that the climate is, on the whole, more temperate than that of some other islands in the same latitudes, would lead us to expect the presence of a comparatively large number of European species, or those which are found in the more northern United States, or British North America, and may account for the fact that so small a proportion of species should be identical with those from neighbouring islands.
In Central America only a few small collections have been made, which indicate a sub-tropical region.
From the northern parts of South America, M. Leprieur collected in French Guiana.[W] Southwards of this, Spruce collected in the countries bordering on the River Amazon, and Gardner in Brazil,[X] Gaudichaud in Chili and Peru,[Y] Gay in Chili,[Z] Blanchet in Bahia,[a] Weddell in Brazil,[b] and Auguste de Saint Hiliare[c] in the same country. Small collections have also been made in the extreme south. All these collections contain coriaceous species of _Polyporus_, _Favolus_, and allied genera, with _Auricularini_, together with such _Ascomycetes_ as _Xylaria_, and such forms of _Peziza_ as _P. tricholoma_, _P. Hindsii_, and _P. macrotis_. As yet we cannot form an estimate of the extent or variety of the South American flora, which has furnished the interesting genus _Cyttaria_, and may yet supply forms unrecognized elsewhere.
The island of Juan Fernandez furnished to M. Bertero a good representative collection,[d] which is remarkable as containing more than one-half its number of European species, and the rest possessing rather the character of those of a temperate than a sub-tropical region.
Australasia has been partly explored, and the results embodied in the Floras of Dr. Hooker and subsequent communications. In a note to an enumeration of 235 species in 1872, the writer observes that "many of them are either identical with European species, or so nearly allied that with dried specimens only, unaccompanied by notes or drawings, it is impossible to separate them; others are species which are almost universally found in tropical or sub-tropical countries, while a few only are peculiar to Australia, or are undescribed species, mostly of a tropical type. The collections on the whole can scarcely be said to be of any great interest, except so far as geographical distribution is concerned, as the aberrant forms are few."[e]
The fungi collected by the Antarctic Expedition in Auckland and Campbell's Islands, and in Fuegia and the Falklands,[f] were few and of but little interest, including such cosmopolitan forms as _Sphæria herbarum_ and _Cladosporium herbarum_, _Hirneola auricula-judæ_, _Polyporus versicolor_, _Eurotium herbariorum_, etc.
In New Zealand a large proportion have been found, and these may be taken to represent the general character of the fungi of the islands, which is of the type usually found in temperate regions.[g]
The fungi of Asia are so little known that no satisfactory conclusions can be drawn from our present incomplete knowledge. In India, the collections made by Dr. Hooker in his progress to the Sikkim Himalayas,[h] a few species obtained by M. Perottet in Pondicherry, and small collections from the Neilgherries,[i] are almost all that have been recorded. From these it may be concluded that elevations such as approximate a temperate climate are the most productive, and here European and North American genera, with closely allied species, have the preponderance. The number of _Agaricini_, for instance, is large, and amongst the twenty-eight subgenera into which the genus _Agaricus_ is divided, eight only are unrepresented. Casual specimens received from other parts of India afford evidence that here is a vast field unexplored, the forests and mountain slopes of which would doubtless afford an immense number of new and interesting forms.
Of the Indian Archipelago, Java has been most explored, both by Junghuhn[j] and Zollinger.[k] The former records 117 species in 40 genera, Nees von Esenbeck and Blume 11 species in 3 genera, and Zollinger and Moritzi 31 species in 20 genera, making a total of 159 species, of which 47 belong to _Polyporus_. Léveillé added 87 species, making a total of 246 species. The fungi of Sumatra, Borneo, and other islands are partly the same and partly allied, but of a similar tropical character.
The fungi of the island of Ceylon, collected by Gardner, Thwaites, and König, were numerous. The Agarics comprise 302 species, closely resembling those of our own country.[l] It is singular that every one of the subgenera of Fries is represented, though the number of species in one or two is greatly predominant. _Lepiota_ and _Psalliota_ alone comprise one-third of the species, while _Pholiota_ offers only a single obscure species. The enumeration recently published of the succeeding families contains many species of interest.
In Africa, the best explored country is Algeria, although unfortunately the flora was never completed.[m] The correspondence between the fungi of Algeria and European countries is very striking, and the impression is not removed by the presence of a few sub-tropical forms. It is probable that were the fungi of Spain known the resemblance would be more complete.
From the Cape of Good Hope and Natal collections have been made by Zeyher,[n] Drége, and others, and from these we are enabled to form a tolerable estimate of the mycologic flora. Of the _Hymenomycetes_, the greater part belong to _Agaricus_: there are but four or five _Polypori_ in Zeyher's collection, one of which is protean. The _Gasteromycetes_ are interesting, belonging to many genera, and presenting two, _Scoleciocarpus_ and _Phellorinia_, which were founded upon specimens in this collection. _Batarrea_, _Tulostoma_, and _Mycenastrum_ are represented by European species. There are also two species of _Lycoperdon_, and one of _Podaxon_. Besides these, there is the curious _Secotium Gueinzii_. The genus _Geaster_ does not appear in the collection, nor _Scleroderma_. Altogether the Cape flora is a peculiar one, and can scarcely be compared with any other.
At the most, only scattered and isolated specimens have been recorded from Senegal, from Egypt, or from other parts of Africa, so that, with the above exceptions, the continent may be regarded as unknown.