Section C—Chairman's Address
Taxonomic Problems of Some Hymenomycetes
It is proposed in this address to discuss some problems which have arisen in the course of monographing Australian and New Zealand species of wood-inhabiting basidiomycetes. Examples have been selected from the families Polyporaceae and Thelephoraceae, since they well illustrate difficulties which have arisen in connection with accurate delimitation of genera and identification of species.
The family was erected by Fries in Systema Mycologicum, volume I of which was published in 1821. Under the International Rules of Botanical Nomenclature this work becomes the starting point for nomenclature of the family; consequently names which were published prior to that date may be disregarded. Under this family Fries placed species in which the hymenium of the fructification is carried in narrow pores inserted in the usually ventral portion. In the three volumes of the Systema Fries recognised five genera—Cyphella, Daedalea, Lenzites, Polyporus and Solemnia, though he dispersed them among several families; and in later works added Favolus and Irpex (1828), Cyclomyces (1830). Trametes (1838) and Polystictus (1851). Ten genera in all.
Genera were delimited by Fries on such macrofeatures as pore form and texture of the context; species on pileus shape, size, colour, and whether stalked, sessile, or resupinate. Such were possibly adequate features for the relatively few species then known from Europe: in fact, there was little else to employ, as at that period the microscope was little better than a toy. As more species were recognized, especially when the wealth of forms from the tropics were collected, it became evident to students that the few genera of Fries were inadequate for taxonomic purposes. Furthermore, since Fries did not define his genera adequately, their interpretation has subsequently provided a problem for taxonomists, aggravated by the fact that type species and type collections were not indicated, nor in many cases preserved.
Consequently later mycologists attempted to improve upon the several systems published by Fries, notably Karsten (1879. 1881. 1889). Quelet (1886), Patouillard (1900). Murrill (1907–08, 1914, 1942). Ames (1913), Donk (1933), Pilat (1936–1942) Cooke (1940), and Bondarzew & Singer (1941). Most arranged genera upon macrofeatures, their numbers ranging from a modest 16 to 90. None of these classifications enabled one to identify species accurately, or defined genera so that species could be placed under them without some degree of confusion. In the result when I commenced to study Australasian species in 1946 a thorough search was made of the literature to ascertain if other methods of classifying genera and species could be found. A promising field appeared in two papers published by E. J. H. Corner (1932a, 1932b), who dealt with anatomical details of a few species, a new field of study in the family. Some six months were spent examining anatomical details of 350
species then available. It was found that genera could be defined by certain anatomical features; and species identified so readily that later when working through Australian and New Zealand collections in Kew herbarium, it was possible to name all but half a dozen despite that most were represented by single specimens, often poorly preserved, or fragmentary.
Corner, in his two now classical papers, described the anatomy of three species. He showed that in “Polystictus” xanthopus three series of hyphae composed the fructification. These he named skeletal, binding, and generative. Skeletal hyphae provided a rigid framework, binding hyphae held the first together and formed most of the tramal walls upon which the hymenium developed, generative hyphae supplied the hymenium and surface tissues. In Fomes laevigatus and F. senex Corner. found that there were two hyphal series. skeletal and generative. He therefore postulated that one, two, or three hyphal systems were involved in forming the fructification of different species in the family. These he named respectively monomitic, dimitic and trimitic hyphal systems, thus:
|Hyphal System||Hyphal Series|
|Monomitic||Generative hyphae only.|
|Dimitic||Skeletal and Generative hyphae.|
|Trimitic||Skeletal, Binding and Generative hyphae.|
My studies (1947–1950) confirmed those of Corner. They showed that three hyphal systems were involved in producing the fructification of different species, exactly as Corner had forecast; that not more than three were involved. Furthermore, certain fundamental differences were noted between species with brown and with hyaline hyphae (as seen under the microscope), mainly in the presence or absence of clamp connections and correspondingly of the number of nuclei in the hyphal cell. These differences are fundamental, and useful as aids in segregating certain genera and species into related groups. They are shown in tabular form, thus:
Monomitic Hyphal System: Champ connections present in hyaline hyphae (or if absent replaced with bridging hyphae); clamp connections absent from species with brown hyphae.
Dimitic Hyphal System: Clamp connections present in hyaline hyphae (or replaced with bridging hyphae); clamp connections absent from species with brown hvphae.
Trimitic Hyphal System: Clamp connections present in generative hyphae of species with hyaline or brown skeletal and binding hyphae.
Once these and certain other microfeatures are mastered, and providing spores and basidia are present, any polypore can be identified from a mere fragment, because such features are constant, and do not change with habitat, or climate, as do most macrofeatures.
Let us now consider briefly how anatomical features may be used in delimiting genera. Out of the scores of generic names which have been proposed it has been necessary to select sufficient for an adequate classification. About 25 genera can be separated on features which are both constant and can be defined accurately. Some genera could be further subdivided on minor micro-features, but as yet there appears to be little advantage in maintaining a large number of genera for what is after all a relatively small family.
Most selected are well established names: but in the past have had no concise application. Consider. for example, the genus Fomes as used in its broad sense to embrace perennial species with round pores arranged in strata.
Though used by Fries in 1838 as a sectional name, Fomes was not employed in a generic sense until so used by Kickx in 1867. Under Fomes Kickx placed, in that order, F. salicinus, F. igniarius, F. fomentarius and F. lucidus. One is therefore the type species, but which? Some workers have arbitarily chosen F. igniarius, others, F. fomentarius without realizing that they are generically different plants. Two species possess brown, one hyaline hyphae; two possess trimitic hyphal systems with clamp connections; two dimitic hyphal systems without clamp connections. F. salicinus and F. igniarius possess brown hyphae, dimitic hyphal systems and are without clamp connections. They are therefore co-generic, and as the former has not been proposed as a type it may be disregarded further. F. fomentarius has brown hyphae and a trimitic hyphal system with chlamp connections in the generative hyphae. It is therefore not co-generic with F. igniarius. Upwards of 150 species of Fomes with brown hyphae and dimitic hyphal systems are known: whereas there are only about eight with brown hyphae and trimitic hyphal systems, as in F. fomentarius. Consequently stability in nomenclature would best be secured by regarding F. igniarius as the type species, since it also agrees most closely with the general interpretation of the genus. A generic name for F. fomentarius lies to hand in Elfvingiella which Murrill (1914) erected with it as type species. Fomes lucidus, on the other hand. has a trimitic hyphal system with hyaline hyphae and peculiar roughwalled spores, which may be termed ganodermous. It does not agree with the others as is evident, so must be placed under some other name. To it Karsten (1881) gave the name of Ganoderma. with G. lucidum as type species. So we have no less than three genera for the four species placed by Kickx under Fomes.
Two other species of world-wide distribution, usually placed under Fomes. now require consideration, namely F. applanatus and F. annosus. Both possess dimitic hyphal systems without clamp connections in the generative hyphae. But they are not Fomes, as defined above, nor co-generic with one another. For in F. applanatus skeletal hyphae are brown, freely branched in a peculiar manner—a condition found only in a few related species—and spores are ganodermous; whereas in F. annosus skeletal hyphae are hyaline. unbranched, amylaceous, and pores are smooth and hyaline. Karsten (1881, 1889) had provided generic names for both, with these species as types, namely Elfvingia for the former. Fomitopsis for the latter.
Thus the old genus “Fomes” consists of five genera, which may be defined accurately by the following characters:
|Hyphal system dimitic, without clamp connections.|
|Hyphae hyaline, spores smooth||Fomitopsis (F annosa)|
|Hvphae brown, spores smooth||Fomes (F. igmarius)|
|Hyphae brown, spores ganodermous||Elfcingia (E. applanta)|
|Hyphal system trimitic. generative hyphae with clamp connections.|
|Hyphae hyaline. spores ganodermous||Ganoderma (G. lucidum)|
|Hyphae brown spores smooth||Elfvingiella (E. fomentaria)|
(Certain other associated microfeatures are not listed.)
Friesian genera concerning which there has been uncertainty of interpretation, or were used to embrace species of several genera, can be defined similarly to include related species only. Polyporus, Lenzites and Daedalea have been used by most workers to contain species with hyaline or brown hyphae and monomitic. dimitic and trimitic hyphal systems. Polystictus, introduced by Fries in 1851
and regarded by most workers as a receptacle for thin species of Polyporus, has not been clearly defined, then or subsequently. And Trametes, erected by Fries in 1836, has remained a puzzle genus since. By aid of the features discussed it is possible to define them accurately and precisely, though as yet the position of Polystictus is doubtful. A rough guide to their diagnostic features is:
|Hyphae hyaline; with clamp connections or bridging hyphae.|
|Hyphal system monomitic or dimitic.|
|Pores round or oval.|
|Fructifications pileate||Polyporus Mich. ex Fr.|
|Fructifications resupinate||Poria (Pers.) Gray|
|Pores becoming irpiciform with a permanent poroid border||Irpex Fr.|
|Hyphal system trimitic, with clamp connections.|
|Pores round or oval||Coriolus Quel.|
|Pores lamellar or labrynthiform||Lenziles Fr.|
|Hyphal system monomitic, without clamp connections.|
|Setae absent from the hymenium||Coltricia Gray|
|Setae present in the hymenium||Inonolus Karst.|
|Hyphal system dimitic, without clamp connections.|
|Spores smooth||Hapalopilus Karst|
|Spores ganodermous||A mauroderma Murr.|
|Hyphal system trimitic, with clamp connections.|
|Pores round||Trametes Fr.|
|Pores lamellar or labrynthiform||Daedalea Pers. ex Fr.|
(A few genera, mainly of tropical distribution, have been excluded.)
In many of the old genera, difficulty arises in deciding the type species. Reasons are that early workers did not designate such, and as our concepts have changed because of the differential features employed, type species chosen arbitarily by later workers are not necessarily suitable for the purpose, as has been shown when discussing the type species for Fomes.
Anatomical features are equally useful in delimiting species, especially variable species, as to macrofeatures, not uncommon in tropical and subtropical regions; or resupinate plants placed under Poria or Fuscoporia. These latter are, incidentally, merely genera of convenience, the former containing resupinate forms of Polyporus, the latter of Fomes.
“Polyporus” occidentalis was found in Kew herbarium filed under five genera and twenty species; yet the microstructure of this common subtropical species shows it to be a Coriolus close indeed to our common C. hirsutus Daedalea trabea may develop fructifications with poroid. daedaloid, lamelloid or irpicioid hymenia. grow pileate or resupinate, range in colour from orange, through grey, ferruginous, to umber. In consequence it bears a formidable list of synonyms, because of these variable macrofeatures; yet has a microstructure so distinctive, that identification of each specimen is certain, no matter how diverse its gross morphology. A common Australasian species, “Polyporus” ochrolencus, is found in literature under Polyporus, Polystictus, Fomes, Trametes, and Ungulina, and bears upwards of twenty-five synonyms. Its microstructure shows it to be none of these genera, but a Fomitopsis with characteristic micro-features of that genus. One final example is provided in “Polyporus” schweinitzii, which has a world-wide distribution. Commonly treated as a Polyporus, Polystictus, or Fomes, it has also been described under Daedalea, Phaeolus, Cladomeris and Inodermus. Its microstructure is unmistakably that of Coltricia, as one section will show under a microscope.
This second family has been selected to show that, in the fungi, even within the same order, one cannot take diagnostic features from one family and apply them indiscriminately to others. The only links species possess with the Polyporaceae are that both are Basidiomycetes and most wood-inhabiting. The one constant feature upon which the family is based is that the hymenium forms a continuous membrane over the surface of the context. It is composed of basidia and paraphyses arranged in a palisade, alone or associated with ancillary organs of many diverse types Most species are resupinate, a few pileate, then resembling thin polypores. Most look alike, save in point of colour, resembling as much as anything, thin coats of paint lying upon bark of dead or living branches.
In 1951 I worked through all collections of the family in Kew herbarium. My objectives were to study described species of the world so that Australasian collections could be named correctly, ascertain those features upon which a natural classification could be based, and if hyphal systems could be so employed, as with the polypores. Results of these studies showed that hyphal systems were not so well defined in the family that use could be made of them in generic classification. On the other hand, it was found that most genera could be segregated on two groups of characters. Interpretation of these taxes the skill of the mycologist; for it is necessary to prepare thin sections, employ various types of reagents, treat sections of some species to remove obscuring mineral matter, dissect others apart to study the various organs. Consequently critical studies of members of the family are possible only by the skilled microscopist with adequate experience of microtechnique.
Because of the few features employed by earlier workers in generic and specific delimitation, there is a great deal of confusion in literature as to names for both genera and species. The position has been made more difficult in that, as with the polypores, most early workers did not retain type collections, or distributed several species under one common name. In their absence workers have tried to guess at what many early species represented, with chaotic results.
The family may be divided into subfamilies and tribes by the arrangement of tissues of the context, and into genera by the presence or absence of the following ancillary organs, with to a lesser extent hyphal systems, hyphal colour, types of spores, and the like.
1.Gloeocystidia Unicellular organs of diverse shape, but usually fusiform or subclavate, commonly present in the hymenium but sometimes scattered through the context, gloeocystidia are the only ancillary organs in Corticium and Cytidia; accompany dichophyses in Vararia, cystidia in Peniophora, asterophyses in Asterostroma, and acanthophyses in Aleurodiscus. Their function is unknown; possibly they act as storage organs since, when fresh at least, they are filled with oily contents coloured yellow, when old are usually empty and often collapsed.
2.Vesicles. Usually one-celled and resembling gloeocystidia save in size and shape, these bodies are present in three species of Corticium, and one Stereum. In one Corticium they are two-celled, with the septum encircled by a band of aculeate processes.
3.Cystidia. Hyaline organs, not unlike gloeocystidia in shape, present in species of Peniophora, cystidia are of two types. Typical forms, termed ‘metuloids’ by Cooke, are coated with refractive crystals and therefore conspicnous in sections; in the second type they are commonly naked (some are capped with a crown of crystals) and project for the greater part of their length above the hymenium. Some species of Pellicularia and Coniophora bear bodies which have been termed cystidia. They are septate, coloured, and some bear exterior warts of mucilage. Because they differ from true cystidia as defined above, I have named them septocystidia.
4.Acanthophyses. Developed either from modified paraphysate hyphae arising from generative hyphae. or branched skeletal hyphae. they form the bulk of the hymenial layer in all species of Aleurodiscus, and one Stereum. The apices may be crowned with numerous delicate processes or brief branchlets, or both apices and stems covered with spines either straight or hooked at their apices. Or acanthophyses may be branched freely, thickwalled, with the apical part or the whole bearing digitate processes, spines, or both. Simple forms are associated with pileate species, branched forms with resupinate plants.
5.Dichophyses. In the hymenial layer and/or context of species of Vararia are present dendriform structures so characteristic that species may be placed in the genus immediately sections are examined. In simple forms each dichophysis consists of a simple stem from which arise a cluster of branches. These In turn branch, often dichotomously, and branchlets terminate in long or short acuminate apices. The whole resembles a delicate shrub, with tissues staining deeply with aniline blue. Compound dichophyses are present in two species. Here the main stem traverses the stratose tissues producing at intervals branches which become branched to form either dendriform structures like those described, or remain unbranched and traverse the tissues laterally.
6.Asterophyses. Confined to Asterostroma of this family, these structures form the bulk of the context and hymenial layer. In the context they are coloured. stellate, with 5—9 long arms tapering to fine sometimes bifid apices; in the hymenial layer they are small, hyaline, and composed of short lateral spines arising from an inflated median centre.
7.Setae. The genus Hymenochaete is recognized readily by its coloured aculeate setae which usually project above the surface and give to it a velvety appearance when viewed under a lens. Usually crowded in the hymenium. in other species setae may be scattered or arranged in tufts; and in perennial plants form a series of zones.
8.Pseudosetae. In Duportella the hymenium is crowded with a dense palisade of bodies which simulate setae but differ in that they are merely slightly modified ends of upturned skeletal hyphae.
9.Fascicles. Three genera bear fascicles which, arising from the base of the conext, pierce the hymenial layer to emerge for some distance. Composed of bundles of hyphae closely compacted, sometimes crystal coated or enclosing columns of crystals, they are conspicuous and readily seen under a lens. Composed of hyaline hyphae in Mycobonia and Epithele, fascicles are of brown hyphae in Veluticeps.
10.Conducting Vessels. Several species of Stereum contain modified skeletal hyphae which pass from the context to the surface of the hymenium.
They contain thick granular contents which may exude as yellow or red drops when the surface is damaged. In sections they stain with aniline blue, and often exude their contents as long irregular amorphous filaments. Because of their contents they have also been termed lactiferous ducts.
11.Hyphal Systems and Clamp Connections. Though not as clearly defined as in the polypores, nevertheless hyphal systems are of aid in diagnosis, mainly of species. The following table shows these features for species of each genus. Hyphae are brown in Coniophora, Thelephora, Duportella and Hymenochaete and in a few species of Solenia (1), Corticium (1), Peniophora (3) and Stereum (4). In the others hyphae are hyaline.
[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]
|No. of Species.||M+||M-||D+||D-|
|[ unclear: ]||7||7|
(M = monomitic; D = dimitic; + with and - without clamp connections.) A brief key is given below of genera present in New Zealand, modified and amended from a paper recently published (Cunningham. 1953).
Key To Genera Of The Thelephoraceae
A. Sub-family Meruloideae Pileate or resupnate. Hymenal surface shallowly ruguloseporose or rugose; context composed of a base of parallel hyphae and an intermediate layer of woven hyphae; hyphal system monomitic or dimitic, clamp connections present or absent. Hymenal layer containing basidia. paraphyses and in some species gloeocystidia. Spores smooth.
(a) Context hyphae and spores hyaline; gloeocystidia present in some species 1. Merulius Pers. ex Fr. (b) Context hyphae and spores brown; gloeocystidia absent 2 Scrpula Pers. ex Gray
B. Sub-family Cyphelloiideae: Pileate. Fructifications cylindrical. cupulate and sessile, or obconic and pendent from the vertex; hymenial surface even, concave, lining interior of pilei, context composed of compacted parallel hyphae radiate from the point of attachment; hyphal system monomitic, with clamp connections. Hymenial layer containing basidia and paraphyses. Spores smooth.
(a) pilei crowded upon a subiculum composed of woven hyphae effused over the substratum 3. Solenia Pers. (b) pilci attached by a brief base, scattered. Sessile subiculmn absent 4. Cyphella Fr.
C. Sub-family Thelephoroideae: Pileate when fructifications are stipitate or sessile, on resupinate and adnate. Hymenial surface even or pierced by fascicles of hyphae.
1. Tribe Corticeae: Resupinate (save in a few species of Peniophora); context composed of a base of parallel hyphae and an intermediate layer of upright hyphae; hyphal system monomitic (save in a few species of Peniophora), hyphae commonly hyaline. Hymenial layer containing basidia and paraphyses with sometimes in addition gloeocystidia, dichophyses, asterophyses, cystidia, hyphal fascicles, or septocystidia. Spores hyaline, smooth or in a few species verruculose.
(1) Basidia and paraphyses arising in small clusters from lateral branches of repent hyphae; hyphal system monomitic; with or without clamp connections; septocystidia sometimes present 5. Pellicularia Cke. (2) Basidia and paraphyses forming a continuous hymenium with in addition one or more types of ancillary organs. (a) Hymenial layer sometimes containing gloeocystidia; hyphae with or without clamp connections 6 Corticium Pers. (b) Hymenial layer containing dichophyses and in some species gloeocystidia; hyphae with clamp connections 7 Vararia Karst. (c) Hymenial layer containing asterophyses and gloeocystidia; hyphae without clamp connections 8 Asterostroma Mass (d) Hymenial layer containing cystidia and in some species gloeocystidia; hyphal system monomitic or dimitic, with or without clamp connections 9 Peniophora Cke. (e) Hymenial layer containing fascicles of projecting hyaline hyphae. (i) Pileate. with clamp connections 10 Mycobonia Pat. (ii) Resupinate; with or without clamp connections 11 Epithele Pat. (f) Hymenial layer containing projecting fascicles of coloured hyphae: with or without clamp connections 12. Veluticeps Cke.
II. Tribe Stereae: Pileate when fructifications are stipiate or sessile, or resupinate in a few species of Aleurodiscus; context composed of densely compacted parallel hyphae radiating from the base; hyphal system monomitic or dimitic; hyphae commonly hyaline, coloured in a few species of Stereum; hymenial layer containing basidia and paraphyses alone or associated with conducting vessels, gloeocystidia, vesicles or acanthophyses. Spores hyaline, smooth or verruculose.
(a) Pileate. Fructifications ureolate, infundibuliform, Flabelliform, spathulate or effused-reflexed; hymenial layer composed of basidia and paraphyses alone or with conducting vessels, gloeocystidia, vesicles or acanthophyses 13 Slcreum Pers. ex Fr. (b) Pileate when pezizoid, discoid, or flabelliform. or resupinate and effused; hymenial layer containing basidia, paraphyses, acanthophyses and gloeocystidia 14 Aleurodiscus Rabenh. (c) Pileate when discoid or patelliform. attached by a narrow ventral base; hymenial layer containing basidia, paraphyses and in some species gloeocystidia 15 Cytidia Quel.
III. Tribe Thelephoreae: Pileate or resupinate; context composed of intertwined hyphae with walls coloured brown; hyphal system monomitic or dimitic, with or without clamp connections; hymenial layer containing basidia. paraphyses and sometimes septocystidia. Spores coloured.
(a) Pileate. Hyphal system monomitic. clamp connections present: septocystidia absent; spores verrucose or echinulate 16. Thelephora Ehrh ex Fr.
(b) Resupinate. Hyphal system monomitic or dimitic, hyphae without clamp connections; septocystidia sometimes present; spores smooth 17. Coniophora DC. ex Fr.
IV. Tribe Hymenochaetae: Pileate or resupinate. Context composed of a basal layer of parallel hyphae and an intermediate layer of upright hyphae with coloured walls; hyphal system monomitic or dimitic, with or without clamp connections; hymenial layer containing basidia, paraphyses, aculeate setae or pseudosetae; spores smooth and hyaline.
(a) Pileate or resupinate; hymenial layer containing brown aculeate setae; hyphal system dimitic (save in one species), without clamp connections 18. Hymenochaete Lev. (b) Resupinate; hymenial layer containing pseudosetae; hyphal system dimitic, with clamp connections 19 Duportella Pat.
Ames, Adeline, 1913. Annales Mycologici, 11, 211–253.
Bondarzew, A. & Singer. R., 1941. Annales Mycologici, 39, 43–65.
Cooke, W. B., 1940. Lloydia, 3, 81–104.
Corner, E. J. H., 1932a. Annals of Botany, 46, 71–111.
—— 1932b. Transactions of British Mycological Society, 17, 51–81.
—— 1953. Phytomorphology, 3, 152–167.
Cunningham, G. H., 1947a. N.Z. Journal of Science & Technology, 28, 238–251.
—— 1947b. Plant Diseases Division Bulletin No. 72, 43 pp.
—— 1948a. Plant Diseases Division Bulletin, No. 73, 14 pp.
—— 1948b. Plant Diseases Division Bulletin, No. 74, 39 pp.
—— 1948c. Plant Diseases Division Bulletin, No. 75, 10 pp.
—— 1948d. Plant Diseases Division Bulletin No. 76, 8 pp.
—— 1948e. Plant Diseases Division Bulletin, No. 77, 10 pp.
—— 1948f. Plant Diseases Division Bulletin, No. 78, 5 pp.
—— 1948g. Plant Diseases Division Bulletin, No. 79, 24 pp.
—— 1948h. Plant Diseases Division Bulletin, No. 80, 10 pp.
—— 1949a. Plant Diseases Division Bulletin, No. 81, 24 pp.
—— 1949b. Plant Diseases Division Bulletin, No. 82, 8 pp.
—— 1950a. Plant Diseases Division Bulletin, No. 83. 12 pp.
—— 1950b. Proceedings of Linnean Society of New South Wales, 75, 214–249.
—— 1953. Transactions of Royal Society of New Zealand, 81, 165–188.
Donk, M. A., 1933. Nederl. Mykol. Veerenig., Med. 23, 1–278.
Fries, E. M., 1821. Systema Mycologicum, 1, 520 pp.
—— 1822 Systema Mycologicum, 2, 620 pp.
—— 1829. Systema Mycologicum, 3, 524 pp.
—— 1828. Elenchus Fungorum, 1, 1–238; 2, 1–154.
—— 1830. Linnaea, 5, 512.
—— 1838. Epicrisis systematis mycologici seu synopsis Hymenomycetum, 1–610.
—— 1851. Nova Acta Soc. Sci Upsala, 17–136.
Karsten, P. A., 1879. Meddelanden af Societas pro Fauna et Flora fennica, 5, 15–46.
—— 1881 Revue Mycologique, 3, 17–18.
—— 1889. Bidrag till kannedom af Finlands Natur och Folk, 48, 1–470.
Kickx, Jean J., 1867. Flora cryptogamique que des Flandres, 2, 237.
Murrill, W. A., 1907–08. North American Flora, 9, 1–131.
—— 1914. Northern Polypores, 64 pp.
—— 1942. Mycologia, 34, 595–596.
Patouillard, N., 1900. Essai taxonomique sur les familles et les genres des Hymenomycetes, 184 pp.
Pilat, A., 1936–1942. Atlas des Champignons de l'Europe. 3, 1–472.
Quelet, L., 1886. Enchiridion fungorum, 352 pp.