Exobasidium Weron.
Helicobasidium Pat.
Cyph.e.l.la Fries.
Friesula Speg.
Cora Fries.
Rhipidonema Matt.
V.--CLAVARIACEae (Clavariei).
GENERA.
Spara.s.sis Fries.
Acartis Fries.
Clavaria Vaill.
Calocera Fries.
Lachnocladium Lev.
Pterula Fries.
Ptifula Pers.
Pistallaria Fries.
Physalacria Peck.
VI.--TREMELLACEae (Tremellini)
GENERA.
Auricularia Bull.
Hirneola Fries.
Platygloea Schroet.
Exidia Fries.
Ulocolla Bref.
Craterocolla Bref.
Femsjonia Fries.
Tremella Dill.
Naematelia Fries.
Gyrocephalus Pers.
Delortia Pat. & Gail.
Arrhytidia Berk.
Ceracea Cragin.
Guepinia Fries.
Dacryomitra Pul.
Collyria Fries.
GENERA MINUS CERTA.
Hormonyces Bon.
Ditiola Fries.
Apyrenium Fries.
BREFIELD"S CLa.s.sIFICATION OF FUNGI.
A system of cla.s.sification of fungi which is receiving attention from mycologists is that recently presented by the distinguished German author Dr. Oscar Brefield. Dr. Brefield"s exhaustive investigations into the life-history of fungi in general have been such as to ent.i.tle his views to consideration, although the system presents some inconsistencies which may prevent its adoption in its entirety.
According to the Brefield system, as summarized by his colleague Dr. Von Tavel, Fungi are divided into two primary cla.s.ses: (1) the _Phycomycetes,_ or lower fungi nearest like the algae, _consisting of a one-celled thallus with s.e.xual as well as non-s.e.xual modes of reproduction_, and (2) the Mesomycetes and the Mycomycetes, _having a divided or many celled thallus, propagated by non-s.e.xually formed spores_. The Phycomycetes are further divided into two large sections, based on their methods of reproduction, termed, respectively, Zygomycetes and Oomycetes. These include the old typical Mucors, the Peronosporeae or "rotting moulds," once cla.s.sed with the Hyphomycetes, the Saprolegniaceae, "Fish Moulds," of aquatic habit, the Entomophthoraceae, "Insect Moulds," together with some minor groups. The Mesomycetes connect the Phycomycetes with the Mycomycetes. The cla.s.s Mycomycetes is primarily divided into two sections, viz., Ascomycetes and Basidiomycetes, with the Ustilagineae, "s.m.u.t Fungi," in Mesomycetes, forming a transitional group between Phycomycetes and the Basidiomycetal group of the higher fungi.
The Ascomycetes are primarily subdivided into _Exoasci_ and _Carpoasci,_ groups based on the character of the asci. In the first, _Exoasci,_ the asci are naked and borne directly on the mycelium; in the second, _Carpoasci,_ they are enclosed in a wrapper composed of fertile hyphae and sterile threads, having also accessory fruit forms. The first includes Endomycetes and Taphrineae. In the second are included the groups Gymnoasci, Perisporaceae, Pyrenomycetes, Hysteriaceae, Discomycetes, and Helvellaceae.
The Basidiomycetes characterized by the possession of basidia are arranged in two groups, based on the character of the basidia: (1) the Protobasidiomycetes, in which the basidia are septate, divided, and (2) the Autobasidiomycetes, in which the basidia are not divided, and bear a definite number of spores.
The first of these (Protobasidiomycetes) includes the following distinct groups: (1) the Uredineae, "Rust Fungi," which have horizontally divided basidia, always free, never enclosed; (2) the Auricularieae, having basidia somewhat resembling those of the Uredineae, but which are borne in fruit bodies with open hymenia; (3) Pileacreae, having horizontal septate basidia in closed receptacles; and (4) Tremellineae, having vertically divided basidia borne in gymnocarpous receptacles--that is, those in which the hymenium is exposed while the spores are growing.
The Autobasidiomycetes are characterized by undivided basidia, bearing spores only at the apex. This group is subdivided into three sections: (1) Dacryomycetes, which includes the lowest of the Tremelloid forms, with club-shaped basidia, nearly approaching the true Hymenomycetal type, together with several groups of minor import; (2) Gasteromycetes; and (3) Hymenomycetes, with Phalloideae placed in the group as a subsection of Gasteromycetes.
The above can only be considered as a very brief abstract of the system of cla.s.sification proposed by Dr. Brefield, but it will serve to give some idea of the principle on which the system is based, which is sufficient for our present purpose. Those who wish to study the system in detail will find it treated in a comprehensive manner in Dr. Von Tavel"s summary as it appears in the _Vergleichende Morphologie der Pilze_, Jena, 1892.
CONIOMYCETES AND HYPHOMYCETES.
In the original cla.s.sification of Fries two of the primary divisions of the sporiferous Fungi were termed, respectively, _Coniomycetes_ and _Hyphomycetes_. This arrangement was accepted by Berkeley, the term _Coniomycetes_ being applied to all fungi in which the naked spores, appearing like an impalpable dust, were the princ.i.p.al feature of the plant, and the term _Hyphomycetes_ to fungi in which the threads or hyphae bearing the spores were the most conspicuous feature.
Coniomycetes, as broadly interpreted by Berkeley and other mycologists of his day, included the Uredineae or "rust fungi," the Ustilagines or "s.m.u.t fungi," the Sphaeropsideae, and the Melanconieae. This arrangement was very unsatisfactory on account of the distinctively different character of the methods of reproduction of the respective groups, and they have since been disa.s.sociated and by some authors ranked as distinct orders or families. Others combine Uredinei and Ustilaginei in one group under the name Hypodermei.
Familiar examples of Uredinei are seen in the rust of the Barberry leaf, etc., and of the Ustilaginei in the "s.m.u.t" of corn and the "bunt" of wheat.
Some authors combine the Sphaeropsideae with the closely allied Melanconieae. M. C. Cooke contends that the _Sphaeropsideae_ should be considered apart from the _Melanconieae,_ on the fundamental basis that the former possess a distinct perithecium, while the latter do not.
The _Sphaeropsideae_ as recently defined by Cooke are "Fungi _possessed of a perithecium, but without asci_, ... sporules or stylospores being produced internally at the apex of more or less distinct supporting hyphae or pedicels, termed sporoph.o.r.es."
The Sphaeropsideae somewhat resemble the Pyrenomyceteae in external characteristics, but differ from them in the absence of asci and paraphyses. Saccardo retains all the species in his Sylloge, but relegates them to an inferior position as imperfect fungi.
The group _Pyrenomycetes_, or _Sphaeriacei_, as at first recognized by _Fries_, included not only the _Sphaeriacei_ and the _Perisporacei_, but also the _Sphaeropsidei_ and _Melanconiaceae_. Later, when ascigerous fungi were separated from stylosporous fungi, this group was revised, the ascigerous species only being retained. As at present limited, the Pyrenomycetes are "_ascigerous_ fungi having the fructification enclosed within a perithecium."
They const.i.tute a very large group, the described species, according to Cooke"s Census of Fungi, numbering not less than 10,500, or at least 1,000 more than all the recorded species of Hymenomycetes. The plants are microscopic in size, and grow upon vegetable or animal substances.
HYPHOMYCETES.
With regard to the Hyphomycetes, Cooke takes the ground that in their internal relations to each other, and their external relations to the remaining orders, the Hyphomycetes are undoubtedly a well-defined and natural group, and should have place as such in a systematic work. It is a large order, containing nearly 5,000 species, mostly parasitic on dead animals and vegetable matter. The spores, termed conidia, are free, as in Hymenomycetes. The species are microscopic in size, and the hyphae are strongly developed. They have no hymenium and no true basidia, and are non-s.e.xual in their reproduction.