Unfortunately no complete or satisfactory account can be given of the geographical distribution of fungi. The younger Fries,[A] with all the facilities at his disposal which the lengthened experience and large collections of his father afforded, could only give a very imperfect outline, and now we can add very little to what he has given. The cause of this difficulty lies in the fact that the Mycologic Flora of so large a portion of the world remains unexplored, not only in remote regions, but even in civilized countries where the Phanerogamic Flora is well known. Europe, England, Scotland, and Wales are as well explored as any other country, but Ireland is comparatively unknown, no complete collection having ever been made, or any at least published. Scandinavia has also been well examined, and the northern portions of France, with Belgium, some parts of Germany and Austria, in Russia the neighbourhood of St. Petersburg, and parts of Italy and Switzerland. Turkey in Europe, nearly all Russia, Spain, and Portugal are almost unknown. As to North America, considerable advances have been made since Schweinitz by Messrs. Curtis and Ravenel, but their collections in Carolina cannot be supposed to represent the whole of the United States; the small collections made in Texas, Mexico, etc., only serve to show the richness of the country, not yet half exhausted. It is to be hoped that the young race of botanists in the United States will apply themselves to the task of investigating the Mycologic Flora of this rich and fertile region. In Central America very small and incomplete collections have as yet been made, and the same may be said of South America and Canada. Of the whole extent of the New World, only the Carolina States of North America can really be said to be satisfactorily known. Asia is still less known, the whole of our vast Indian Empire being represented by the collections made by Dr. Hooker in the Sikkim Himalayas, and a few isolated specimens from other parts. Ceylon has recently been removed from the category of the unknown by the publication of its Mycologic Flora.[B] All that is known of Java is supplied by the researches of Junghuhn; whilst all the rest is completely unknown, including China, Japan, Siam, the Malayan Peninsula, Burmah, and the whole of the countries in the north and west of India. A little is known of the Philippines, and the Indian Archipelago, but this knowledge is too fragmentary to be of much service. In Africa no part has been properly explored, with the exception of Algeria, although something is known of the Cape of Good Hope and Natal. The Australasian Islands are better represented in the Floras published of those regions. Cuba and the West Indies generally are moderately well known from the collections of Mr. C. Wright, which have been recorded in the journal of the LinnÆan Society, and in the same journal Mr. Berkeley has described many Australian species.

It will be seen from the above summary how unsatisfactory it must be to give anything like a general view of the geographical distribution of fungi, or to estimate at all approximately the number of species on the globe. Any attempt, therefore, must be made and accepted subject to the limitations we have expressed.

The conditions which determine the distribution of fungi are not precisely those which determine the distribution of the higher plants. In the case of the parasitic species they may be said to follow the distribution of their foster-plants, as in the case of the rust, smut, and mildew of the cultivated cereals, which have followed those grains wherever they have been distributed, and the potato disease, which is said to have been known in the native region of the potato plant before it made its appearance in Europe. We might also allude to Puccinia malvacearum, Ca., which was first made known as a South American species; it then travelled to Australia, and at length to Europe, reaching England the next year after it was recorded on the Continent. In the same manner, so far as we have the means of knowing, Puccinia Apii, Ca., was known on the Continent of Europe for some time before it was detected on the celery plants in this country. Experience seems to warrant the conclusion that if a parasite affects a certain plant within a definite area, it will extend in time beyond that area to other countries where the foster-plant is found. This view accounts in some part for the discovery of species in this country, year after year, which had not been recorded before; some allowance being made for the fact that an increased number of observers and collectors may cause the search to be more complete, yet it must be conceded that the migration of Continental species must to some extent be going on, or how can it be accounted for that such large and attractive fungi as Sparassis crispa, Helvellas gigas, and Morchella crassipes had never been recorded till recently, or amongst parasitic species such as the two species of Puccinia above named? In the same manner it is undoubtedly true that species which at one time were common gradually become somewhat rare, and at length nearly extinct. We have observed this to apply to the larger species as well as to the microscopic in definite localities. For instance, Craterellus cornucopioides some ten years ago appeared in one wood, at a certain spot, by hundreds, whereas during the past three or four years we have failed to find a single specimen. As many years since, and in two places, where the goat’s-beard was abundant, as it is now, we found nearly half the flowering heads infested with Ustilago receptaculorum, but for the past two or three years, although we have sought it industriously, not a single specimen could be found. It is certain that plants found by Dickson, Bolton, and Sowerby, have not been detected since, whilst it is not improbable that species common with us may be very rare fifty years hence. In this manner it would really appear that fungi are much more liable than flowering plants to shift their localities, or increase and diminish in number.

The fleshy fungi, Agaricini and Boleti especially, are largely dependent upon the character of woods and forests. When the undergrowth of a wood is cleared away, as it often is every few years, it is easy to observe a considerable difference in the fungi. Species seem to change places, common ones amongst a dense undergrowth are rare or disappear with the copsewood, and others not observed before take their place. Some species, too, are peculiar to certain woods, such as beech woods and fir woods, and their distribution will consequently depend very much on the presence or absence of such woods. Epiphytal species, such as Agaricus ulmarius, Agaricus mucidus, and a host of others, depend on circumstances which do not influence the distribution of flowering plants. It may be assumed that such species as flourish in pastures and open places are subject to fewer adverse conditions than those which affect woods and forests.

Any one who has observed any locality with reference to its Mycologic Flora over a period of years will have been struck with the difference in number and variety caused by what may be termed a “favourable season,” that is, plenty of moisture in August with warm weather afterwards. Although we know but little of the conditions of germination in Agarics, it is but reasonable to suppose that a succession of dry seasons will considerably influence the flora of any locality. Heat and humidity, therefore, are intimately concerned in the mycologic vegetation of a country. Fries has noted in his essay the features to which we have alluded. “The fact,” he says, “must not be lost sight of that some species of fungi which have formerly been common in certain localities may become, within our lifetime, more and more scarce, and even altogether cease to grow there. The cause of this, doubtless, is the occurrence of some change in the physical constitution of a locality, such as that resulting from the destruction of a forest, or from the drainage, by ditches and cuttings, of more or less extensive swamps, or from the cultivation of the soil—all of them circumstances which cause the destruction of the primitive fungaceous vegetation and the production of a new one. If we compare the fungal flora of America with that of European countries, we observe that the former equals, in its richness and the variety of its forms, that of the phanerogamous flora; it is probable, however, that, in the lapse of more or fewer years, this richness will decrease, in consequence of the extension of cultivation—as is illustrated, indeed, in what has already taken place in the more thickly peopled districts, as, for example, in the vicinity of New York.”

Although heat and humidity influence all kinds of vegetation, yet heat seems to exert a less, and humidity a greater, influence on fungi than on other plants. It is chiefly during the cool moist autumnal weather that the fleshy fungi flourish most vigorously in our own country, and we observe their number to increase with the humidity of the season. Rain falls copiously in the United States, and this is one of the most fruitful countries known for the fleshy fungi. Hence it is a reasonable deduction that moisture is a condition favourable to the development of these plants. The Myxogastres, according to Dr. Henry Carter, are exceedingly abundant—in individuals, at least, if not in species—in Bombay, and this would lead to the conclusion that the members of this group are influenced as much by heat as humidity in their development, borne out by the more plentiful appearance of the species in this country in the warmer weather of summer.

In the essay to which we have alluded, Fries only attempts the recognition of two zones in his estimate of the distribution of fungi, and these are the temperate and tropical. The frigid zone produces no peculiar types, and is poor in the number of species, whilst no essential distinction can be drawn between the tropical and sub-tropical with our present limited information. Even these two zones must not be accepted too rigidly, since tropical forms will in some instances, and under favourable conditions, extend far upwards into the temperate zone.

“In any region whatever,” writes Fries, “it is necessary, in the first instance, to draw a distinction between its open naked plains and its wooded tracts. In the level open country there is a more rapid evaporation of the moisture by the conjoined action of the sun and wind; whence it happens that such a region is more bare of fungi than one that is mountainous or covered by woods. On the other hand, plains possess several species peculiar to themselves; as, for example, Agaricus pediades, certain Tricholomata, and, above all, the family Coprini, of which they may be regarded as the special habitat. The species of this family augment in number, in any given country, in proportion to the extent and degree of its cultivation; for instance, they grow more luxuriantly in the province of Scania, in Sweden—a district farther distinguished above all others by its cultivation and fertility. In well-wooded countries moisture is retained a much longer time, and, as a result, the production of fungi is incomparably greater; and it is here desirable to make a distinction between the fungi growing in forests of resinous-wooded trees (ConiferÆ) and those which inhabit woods of other trees, for these two descriptions of forests may be rightly regarded, as to their fungaceous growths, as two different regions. Beneath the shade of ConiferÆ, fungi are earlier in their appearance; so much so, that it often happens they have attained their full development when their congeners in forests of non-resinous trees have scarcely commenced their growth. In woods of the latter sort, the fallen leaves, collected in thick layers, act as an obstacle to the soaking of moisture into the earth, and thereby retard the vegetation of fungi; on the other hand, such woods retain moisture longer. These conditions afford to several large and remarkable species the necessary time for development. The beech is characteristic of our own region, but, further north this tree gives place to the birch. Coniferous woods are, moreover, divisible into two regions—that of the pines and that of the firs. The latter is richer in species than the former, because, as is well known, fir-trees flourish in more fertile and moister soils. Whether, with respect to the South of Europe, other subdivisions into regions are required, we know not; still less are we able to decide on the like question in reference to the countries beyond Europe.”[C]

In very cold countries the higher fungi are rare, whilst in tropical countries they are most common at elevations which secure a temperate climate. In Java, Junghuhn found them most prolific at an elevation of 3,000 to 5,000 feet; and in India, Dr. Hooker remarked that they were most abundant at an elevation of 7,000 to 8,000 feet above the sea level.

For the higher fungi we must be indebted to the summary made by Fries, to which we have little to add.

The genus Agaricus occupies the first place, and surpasses, in the number of species, all the other generic groups known. It appears, from our present knowledge, that the Agarici have their geographic centre in the temperate zone, and especially in the colder portion of that zone. It is a curious circumstance that all the extra-European species of this genus Agaricus may be referred to various European subgenera.

In tropical countries it appears that the Agarici occupy only a secondary position in relation to other genera of fungi, such as Polyporus, Lenzites, etc. North America, on the other hand, is richer in species of Agaricus than Europe; for whilst the majority of typical forms are common to both continents, America further possesses many species peculiar to itself. In the temperate zone, so close is the analogy prevailing between the various countries in respect to the Agaricini, that from Sweden to Italy, and as well in England as North America, the same species are to be found. Of 500 Agaricini met with in St. Petersburg, there are only two or three which have not been discovered in Sweden; and again, of fifty species known in Greenland, there is not one that is not common in Sweden. The same remarks hold good in reference to the Agaricini of Siberia, Kamtschatka, the Ukraine, etc. The countries bordering upon the Mediterranean possess, however, several peculiar types; and Eastern and Western Europe present certain dissimilarities in their Agaric inhabitants. Several species, for example, of Armillaria and Tricholoma, which have been found in Russia, have been met with in Sweden only in Upland, that is, in the most eastern province; all the species which belong to the so-called abiegno-rupestres and pineto-montanÆ regions of Sweden are wanting in England; and it is only in Scotland that the species of northern mountainous and pine-bearing regions are met with—a circumstance explicable from the similarity in physical features between Sweden and the northern portions of Great Britain.

The species of Coprinus appear to find suitable habitats in every quarter of the globe.

The CortinariÆ predominate in the north; they abound in Northern latitudes, especially on wooded hills; but the plains offer also some peculiar species which flourish during the rainy days of August and September. In less cold countries they are more scarce or entirely absent. The species of the genus Hygrophorus would at first seem to have a similar geographical distribution to those of the last group; but this is really not the case, for the same Hygrophori are to be found in nearly every country of Europe, and even the hottest countries (and those under the equator) are not destitute of representatives of this wide-spread genus.

The Lactarii, which are so abundant in the forests of Europe and North America, appear to grow more and more scarce towards both the south and north. The same may be stated in regard to Russula.

The genus Marasmius is dispersed throughout the globe, and everywhere presents numerous species. In inter-tropical countries they are still more abundant, and exhibit peculiarities in growth which probably might justify their collection into a distinct group.

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.

From this imperfect summary it will be seen that no general scheme of geographical distribution of fungi can as yet be attempted, and the most we can hope to do is to compare collection with collection, and what we know of one country with what we know of another, and note differences and agreements, so as to estimate the probable character of the fungi of other countries of which we are still in ignorance. It is well sometimes that we should attempt a task like the present, since we then learn how much there is to be known, and how much good work lies waiting to be done by the capable and willing hands that may hereafter undertake it.