INTRODUCTION. organisms which attracted attention of workers all over the. world for a long time. Considering the 'volume of work done

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1 % INTRODUCTION f # The Pyrenomycetes -are a very interesting group of organisms which attracted attention of workers all over the world for a long time. Considering the 'volume of work done on this group of fungi in*countries other than India, there is still ample scope for work on the Indian Pyrenomycetes.. A review of literature reveals that Indian Pyrenomycetes have been worked out from time to time by different workers and their associates. To avoid long listing of names of workers who have just reported or listed names of certain pyrenomycetous fungi from West Bengal and other parts of India, only the names of workers who have done comparatively substantial work are incorporated here. Special mention is made of the workers like : Berkeley, M.J, ( ); Cooke, M.C. ( ); Saccardo, P.A% ( ); Butler, E.J. and others ( ); Sydow, H. and others (1*90 ^ 1937); Theissen, F. and others ( ); Tunstall, A.C. ( );.Thirumalarahar, M.J. and others ( ); Ramakrishnan, T.S. and others ( ); Ramakrishnan, K. and others ( ); Chona, B.L. and others ( ); Bose, S.E. and others ( ); Thind, K.S. and K.S. Waraitch (1969); Tilak, S.T. and others ( ). The states covered by them were mainly Bihar, Uttar Pradesh, Bombay-Maharashtra, Punjab, Madras, Assam, and Mysore. Besides these, compilation work on the Indian fungi has been

2 ) % done by : Butler and Bisby (1931); Mundkur (1938), Subramanian # # and Ramakrishnan, (1956);.Yasudeva (196p); Yasude-va, Tandon and Chandra ( ); and Tilak*and Rao (1970). But from the state 0? West Bengal only a handful of pyrenomyeetous fiingi have been worked out. Mention may be made particularly the work of Berkeley (1856), on the Hypocreaceae and Xylariaceae; Currey (1874) on the Xylaria- ceae; Theissen and Sydow (1915) on the Pfryllachoraceae; 5nd Bal and others ( ) on Meliolaceae. It is evident that there is ample scope for work on the Pyrenomycetes of West Bengal. Hence the present investigation was undertaken to work out the Pyrenomycetes of West Bengal. In course of the «present investigation extensive field studies were made and. collection trips were undertaken in different parts of West Bengal, both in plains aijd hills. HISTORICAL BACKGROUND Historically speaking, the name Pyrenomycetes was introduced by Fries (1823), who regarded the possession of a perithecium containing asci as an essential character of the members of the group. But Fries treated Pyrenomycetes as an order under the class Basidiomycetes. The Pyrenomycetes of Fries was emended by de Notaris (1844) and was followed by Saccardo (1882), designated as

3 Pyrenomyceteae which included fungi^possessing ascus-hearing perithecia, usually growing on plants, rarely on animals, never truly on the.ground. Sacpardo divided Pyrenomycetes into seven families Perisporiaceae, Sphaeriaceae, Hypom creaceae, Dothideaceae, Microthyriaceae, Lophiostomatiaceae and Hysteriaceae. m * * Winter (1887) considered the Pyrenomycetes as one $f the orders of class Ascomycetes. He. subdivided his order Pyrenomycetes into 4 suborders: Perisporiaceae, Hypocreaceae, Sphaeriaceae and Dothideaceae. He further subdivided suborder Perisporiaceae into two families: Dothideaceae and Laboulbenieae; suborder Hypocreaceae with single family Hypocreaceae; suborder Sphaeriaceae intd three principal groups: Chaetomiaceae (with one family Chaetomiceae), t Sordpriaceae (with single family Sordafieae) and'sphaeriaceae into 4 sections. His four sections included: 1st. section having 5 families Trichosphaerieae, Melanommeae, Ceratostomeae, Amphisphaerieae and Lophiostomeae; 2nd section containing single family Cuburbitarieae; 3rd section 5 families (Sphaerelloideae, Pleosporeae, Massarieae, Clypeosphaerieae and Gnomonieae);and 4th section 5 families (Valseae, Melanconideae, Melogrammeae, Diatrypeae and Xylarieae). Winter was followed closely by Ellis and Everhart (1892) too recognised the 4 suborders (Perisporiaceae,

4 Hypocreaceae,* Sphaeriaeeae and Dothideaceae) introduced by Winter. But the^ introduced a new s*uborder Hysteriaceae %hich according them, forms a connecting Jink between the Pyrenomycetes and Dlscoifrycetes ss it shows characters of both these groups. «Lindau (1897) treated the Pyrenomycetes very similar to that of Winter making modifications of*the endings of all the taxonomic categories as : order Pyrenomytetineae un^er which 4 suborders : Perisporiales.(with families : Erysipha- ceae, Perisporiaceae and Microthyriaceae), Hypocreales (with single family Hypocreaceae), Dothideales (with single family Dothideaceae) and Sphaeriales (with the families : Chaetomia- ceae, Sordariaceae, Sphaeriaceae, Ceratostomataceae, Cucurbitariaceae, Coryneliaceae, AmphiSphaeriaceae, Lophios- tomataceae, Mycosphaereilaceae, Pleosporaceae, Massariaceae, Gnomoniaceae, Clypeosphaeriaceae, Val^aceae, Melanconi- daceae, Diatrypaceae, Melogrammataceae, Xylariaceae).'"^' Lindau's division of the Pyrenomycetineae into suborders and * families was based principally upon such characters as colour and consistency of perithecial walls and stroma, presence or absence of strpma and the position of ascocarp in relation to substrate. Lindau's suborders have subsequently been recognized as order and the name Pyrenomycetes has been retained as a general term without definite t axonomic rank to apply to this heterogenous group of fungi. In its general outlines, Lindau's system is usually followed by the present

5 day workers The chief 'tendency* in the* work (Jf the past fifty years. # * has been toward the recognition of a distinct series of ascostromatic forms in the Pyrenomycetes. Typically, the ascoearp of the Pyrenomycetes has been considered to be a perithecium, a hollow, flask-shaped structure opening by an apical ostiole and lined with a* single layer of asci inter- spersed with paraphyses. The perithecia may be separate or united by a stroma in which they are more or less immersed. It was also realized that many fungi included in the Pyrenomycetes do not form perithecia. This is^obvious in large compound forms in which the asci are formed in groups in perithecium-like cavities or locules. in massive stroma and in which it is readily apparent that no differentiated perithecial wall separates the group of asci frojn the surrounding stromal tissue. The ascoearp, therefore, is an*a^jgs- troma containing one to*many locules in which the asci are formed. This, structure was also recognized by Fries (1823). It appears that though Fries just made mention about the stromatic Pyrenomycetes but they were actually widely recognized much later. There has been a gradual tendency among the workers of the Pyrenomycetes to separate the ascostromatic pyrenomycetes and to give them a separate rank. This is evident from the review.of works of Nitschke and Fuckel (1869), Lindau

6 (1897), Hohnel (1907) and others. ^ Theissen and Sydow (1918) emphasized the separate consi- deration of the Pyrenomycetes in which numerous perithecium- like locules are borpe in a strdgia, the' as cocarps lacking true perithecial wall and typical ostioles and being innate, erumpent, or superficial with an innate hypostroma. They included all ascostromatic pyrenomycetes undei; a group Dothidiineae containing orders: Myriangiales, Pseudosphaeriales and Dothideales. Petrak (1923) made some modifications of the order Pseudosphaeriales Included under DothiMineae of Theissen and Sydow (1918). He suggested that the forms that led directly to the Sphaeriales of Lindail should be placed in- that order, others in the Dothideales. and the most primitive forms in the Myriangiales. The ascostromatic forms of Pyrenomycetes were thrsfrghly studied, discussed and categorised into different orders and * families by different workers (Petrak 1923; Arnaud 1918, 1925, 1930, 1931 and others); the details of which are not incorporated here. Only the basic trend of discussion and classification of Ascomycetes with special reference to the Pyrenomycetes and stromatic and non-stromatic Pyreonomycete as a general are treated in this discussion.. Gwynne-Vaughan and Barnes (1927) divided the Ascomycetes

7 into 3 series : Pleetomycetes, Discomycel^es and Pyrenomycetes.. a* They did not separate the ascostrom^ic *forms but placed the ascostromatic Microthyriaceae together with nonstromatic # Erysiphaceae in the Plecto'ascaljes; the. ascostromatic forms like Pleosporaceae, Myco^phaerellaceae, Lophiostomataceae in the Sphaeriales of the Pyrenomycetes, They considered Dothideales having single family Dothid#eaceae like Lindau (1897). Miller (1928) gave further emphasis to the idea that the ascostromatic Pyrenomycetes represent a distinct series of Ascomycetes, He showed that perithecial walls are. specialized structures not homologous with stromal tissue and that paraphyses can not be derived from compressed interthecial stromal tissue. Consequently, he separated this group of Ascomycetes into a series of perithecial forms, the true Pyrenomycetes including only the Sphaeriales, Hypocge^jLes, and Erysiphales, quite distinct from the ascostromatic forms included in.the Myriaqgiales, Pseudosphaeriales, Dothideales, Perisporiaceae and Coryneliaceae. He believed that the Pseudosphaeriales should be included in the Dothideales, Clements and Shear (1931) included all ascostromatic forms in the single order Dothideales which they divided into the families Dothideaceae, Myriangiaceae, and Mycopo- raceae. Most of the genera of the Pseudosphaeriales were retained in the Sphaeriales and Perisporiales, and the

8 «Hemisphaeriales *were considered to be Discomycetes., «Nannfeldt#(1932) divided the Eu^scomycetes into three series : the Plectoascales, Asco'hymeniales, and Ascoloculares. The Discomycetes and Pyrenomycetes with true perithecia were placed in the Aseohymeniales and all the ascostromatic forms in the Ascoloculares. He divided the series Ascoloculares m into 4 orders Myriangiales (with 2 families : Myriangiaceae, * Atichiaceae); Hemisphaeriales (with 5 familie*s : Stigmat«aceae, Polystome11aceae, Microthyriaceae,'Hemisphaeriaceae and Triphopeltaceae); Trichothyriales (with one family Trichothy- riaceae) and Pseudosphaeriales. The order Pseudosphaeriales was further subdivided into 2 suborders: PseuHosphaeriineae (with 4 families : Dothioraceae, Pleosporac'eae, Lophiostom mataceae, Hysteriaceae) and* Mycosphaerellineae (with one family Mycosphaerellaceafe). Bessey (1935) placed the Myriangiales, Dothideales, Hemisphaeriales and Pseudosphaeriales in the ascostromatic series. But he had doubts about the position of Pseudo- sphaeriales. Miller (1941) placed the Myriangiales and Erysiphales among the Plectomycetes and treated Microthyriales (Hemisphaeriales) and Hysteriales as Discomycetes. All ascostromatic forms of Ascomycetes were placed in the two orders Dothideales and Pseudosphaeriales among the Pyrenofcycetes.

9 t 9 «Gaumann (1940) treated all the ascostromatic forms In. a single order fteeifdosph^erialeg. He divided the order, Pseudosphaeriales into 4 families : Dothioraceae, Pseudosphaeriaceae, Mycosphaerell&ceap^ and Dothideaceae. Martin (1945) divi4ed the Ascomycetes into Hemiascomycetes and Euascomycetes. He distributed all ascostromatic pyrenom mycetes into 4 orders (Myriangiales,'Dothideales, Micro- thyriales and Meliolales), of which except the order Myriangiales all were grouped by him as Pyrenomycetes together with Erysiphales and Hypocreales. Hansford (1946) classified the Pyrenomycete-s (only the leaf inhabiting forms) into three orders : Myriangiales, Sphaeriales, and Microthyrtales. He included, the stromatic forms Dothideaceae and Pseudosphaeriaeeae and the nonstromatic Erysiphaceae in a single order Myriangiales; and the ascostromatic forms Mycosphaerellaeeae and Capn«d^ceae in his Sphaeriales. His Microthyrlales is same as Theissen & Sydow with minor modifications. Miller (1949) divided Euascomycetes into Plectomycetes including 3 orders (Eurotiales, Myriangiales and Erysiphales); Pyrenomycetes including 6 orders (Laboulbeniales, Sphaeriales, Hypocreales, Dothideales, Pseudosphaeriales and Microthyriales); and Discomycetes. In the Plectoaseales he placed locule producing ascostromatic Pyrenomycetes - Myrinagiales togethe.r with nonstromatic Eurotiales and Erysiphales. Rest

10 I of stromatic and*nonstromatic Pyrenomyeetes were placed toge- ther under the Pyrenomyeetes. * Gaumann*(1949) classified feuascomycetes just like Nannfeldt (1932) into Pleciascales, Ascoloculares and Ascohymeniales. But'he included the orders Perisporiales phaeriales (Dothioraceae, Pseudosphaeriace&e including * Capnodiaceae, Meliolaceae, Mycosphaerellaceae*, Dothideacoae and Coryneliaceae),and Hemisphaeriales in the Ascoloculares. Luttrell (1951) reviewing the evidence from the development of ascocarp suggested that within the Ascomycetes as a whole the occurrence of the unitunicate and bitunicate ascus could be regarded as a criterion of the first order in establishing a major subdivision of such fungi. He placed the ascostromatic forms having loeules i.e., Myriangiales, Pseu- dosphaeriales, Hysteriales and Trichothyriales in the series Bitunicatae. The second.series Unltunicatae that embraced a large number of Euascomycetes, divided into 4 subseries: * Plectomycetes, Pyrenomyc'etes, Laboulbeniomycetes and Discomy- cetes. He considered the Pyrenomyeetes to be limited to such Ascomycetes which form a true perithecium enclosing fascicles of asci or a hymenial layer of asci (Miller 1928). The Pyrenomyeetes was divided into six orders : Xylariales (with six families : Xylariaceae, Diatrypaceae, Phyllachoraceae, Pyrenulaceae, Clavicipitaceae, Chaetomiaceae); Hypocreales (Erysiphaceae and Perisporiaceae), Myriangiales, Pseudosm

11 t V with single family Hypocreaceae; Diaporthales (with 2 families: Diaporthaceae, Meianospopaceae),; Erysjiphales (with 2 families: * o Erysiphaeeae, Meliolaceae)5 Corpiophorales (with 2 families x Coronophoraceae, Nitschkiatjeae.)., and Cprpeliales with single family CoryneliaCeae. Here he used the name Xylariales instead of Sphaeriales. On the basis of unitunicate asci Lutterell also included some ascostromatic forms in his Unitunicatae. I * Von Arx and Muller (1964) divided the classical Pyreno- mycetes into Unitunicatae and Bitunieatae. In their Unitunicatae they included orders: Plectascales, Phacidiales, Erysiphales, Diaporthales, Clavicipitales, Sphaerj.ales, Tuberales, and the classical Discomysetes. Under the * Bitunieatae they included order : Myrj^ngiales, Dothiorales and Pseudosphaeriales. Von Arx and Muller s Unitunicatae is the same as Ascohymeniales of Nannfeldt (1932) except the orders Plectascales and Phacidiales, % ^ Luttrell (1955) placed all a scostromatic forms in his new subclass, LoculoasQomycetes (Syn. Ascoloculares, Bituni- catae) which was divided into 6 orders : Myriangiales, Dothideales, Trichothyriales, Pleosporales, Hysteriales and Microthyriales. The Pseudosphaeriaceae and Dothioraceae were included in the Dothideales. The Pseudosphaeriales and Dothideales were combined together to form a single order Dothideales. The Pleosporaceae was raised to ordianal rank. The Microthyriales was divided into 2 families : Microthy- riaceae and Micropeltaceae.

12 I V 12 Munk (1957) divided the Pyrenomycetes into Ascohymeniales and Ascolocular^s depending on the nattire of asci whether * 1 * unitunicate or bituriicate respectively. He included all the ascostromatic forms having*locules in the Ascoloculares and the rest of the Pyrenomycetes under the Ascohymeniales. Besides this, he constructed a key to the genera of the Pyrenomycetes combining the stromatid and nonstromatic 4» characters with Saccardo's artificial sporological systeis of spore shape, colour, and septation, which according to Munk has more practical value in identifying different genera. Dennis (1960) divided the Ascomycetes into.euascomycetes «h and Loculoascomycetes based on the type of ascocarp along «with the character of the ascus (unitunicate, oi* bitunic ate). Martin (1961) gave greater importance to stromatic character. He included ascostromatic locule forming members with bitunicate asci under Loculoascomycetes eomprisjwig^f 5 orders (Myriangiales, Microthyri ales, Dothideales, Pleo- sporales and. Hysteriatkes). Ascostromatic locule producing forms having unitunicate asci (orders : Ostropales, Coryne- liales and Coronophorales) were placed close to the Loculoascomycetes. Finally he placed both stromatic and nonstromatic forms possessing either unitunicate or bitunicate asci produced in perithecia or in what may be regarded as modification of this structure in the orders : Laboulbeniales, Meliolales, Erysiphales, Eurotiales, Microascales, Onygenales,

13 Hypocreales, Chaetomiales, Diaporthales, Xylariales, Phaci- * diales, HelotiaHes,* Pezizales apd Tubetfales. *. * The classification of the Pyrenomycetes introduced by Muller and von Arx (1962) is vevy similar to that of von Arx and Muller (1954) except.that they gave more emphasis for the use of taxonomic categories Ascohymeniales and Ascolo- culares in place of Unitunicatag and *Bi.tunicatae respectively. loser (1963) followed basically Nannfeldt's system of classification by placing the orders Myriangiales, Hemisphaeriales, Hysteriales, and Pseudosphaeriales under the Ascoloculares and the orders Coronophorales, Sphaeriales and Clavicipitales under the Ascohymeniales. Dennis (1968) divided* the Ascomycgrtes into Euascomycetes and Loculoascomycetes. He included all the stromatic and nonstromatic Pyrenomycetes having perithecia with true wall together with the Discomycetes under the Euas corny cetew**^n the Loculoascomycetes he put all the ascostromat ic Pyrenomycetes having J.ocules.** MORPHOLOGY AND TERMINOLOGY The members of the Pyrenomycetes possess fructifications of varied forms which again may or not be associated with stroma i.e. stromatic or nonstromatic respectively. Depending on their structural peculiarities and structures borne in

14 I I 14 them, the fructifications have been designated by various * workers in a disfesent manner. In the present work termino- logies have bfeen used following 'the interpretations of leading workers in* respective orders, families and genera; a brief account of which is outlined below. Besides the characters of fructifications, certain structures borne In and on the fructifications and others on hyphae of some * * members of the Pyrenomycetes have also been utilized for* the taxonomic studies of the Pyrenomycetes. Hyphae (sing, hypha) - The hyphae are septate, simple or branched, thin- or thick-walled, hyaline to dark coloured, smooth or bearing some special structures - hyphopodia and setae. The hyphopodia may be one to two-celled.. The presence. of hyphopodia is the characteristic feature of the family Meliolaceae. The presence of setae on mycelia is a taxonomic character in the delimitation of certain genera, e.&. Meliola. Stroma* (pi. stromata) - It is a cushion-like mass of fungal hyphae which may or may not be associated with host tissue, in or on which the fructifications are developed. The stromata may be flattened or crust-like, more or less hemispherically pulvinate, columnar, cylindric, clavate, capitate, or dendroid. They may be sessile to stipitate, totally Immersed or erumpent or totally superficial on the substratum. The stromata may be soft or hard being made

15 # , * up of a pseudoparenchymatous or prosenchyjmatous tissue of definite outline. The fructifications #borne in the stroma may be a typical perithecium with a definite perithecial wall or there may develop in the stjpma cavities (locules) without any definite wall of their own. The details of this aspect will be discussed later. Perithecium (pi. perithecla) - It*is spherical or flask-shaped ascocarp with a short or long beak, characteristic of the Pyrenomyeetes. Each perithecium is provided with a pore or slit at the tip - the ostiole, through which the ascospores escape. The ostiole is formed schizogenously g,nd is lined with fine hyphae - nerjphyses. The perithecium bears unitunicate asci which are arranged in a layer forming hymenium and are intermingled with slender, sterile hyphal threads, the paraphyses free at the tip. The perithecia may be associated with a we11-developed stroma - stromatic*p%ri4hecia: or with some mycelial growth, the subiculum; or may be free from any kind of stroftia or mycelial growth - nonstromatic perithecia. The perithecia may be glabrous or may be set with various types of hairs, appendages or setae of taxonomic importance. The perithecia may be developed singly or in groups. They may be superficial, erumpent or deeply embeded in the substratun. A perithecium regardless of whether it is associated with a stroma or not, has a true wall of its own, a.diagnostic character of the Euascomycetideae.

16 Thyriothecium (pi. thyriothecia) - It is a shield-shaped, *. flattened type erf a»scocarp. It is always superficial and characteristic of the Microthyriafteae and Asterinaeeae. It always contains bitunicate*asc'i. Pseudothecium (pi..pseudothecia) - It is a perithecium- like structure having no periphyses in the opening, but possesses paraphysoids instead of paraphyses. This structure is encountered in the family Pleosporaceae. Ascostroma (pi. ascostromata) - It is the ascocarp of those Pyrenomycetes in which the asci are borne in the stromatic locules instead of true perithecia. The ascostromata may be uniloculate or multiloculate. The uniloculate ascostroma is very similar to perithecia but lacks true wall,'periphyses and paraphyses. Asci borae in an ascostroma are always bi- tunicate. They may or may not be associated with paraphysoids. Ascospores are liberated out through the openings proctuesd * by the breakdown of the stroma surrounding the locules. ** L h* Centrum - The term*centrum was introduced Wehmeyer (1926b) to replace the synonymous term ' nucleus 1, employed by European mycologists since Fries (1823), because of the misleading implications of the latter term. The term includes the ascogenous hyphae and asci and the sterile tissue, occupying the perithecial cavity or locule within which the asci develop. The centrum structure has been employed

17 as an important'taxonomic criterion on the Pyrenomycetes. It was used in the*definition of Pseudos^haeriaceae, Diaportheceae, and Allantosphaeriaceae iby von Hoehnel (1907a, 1917a, 1918b); in the separation*of the Dothideales and Pseudosphaeriales by Miller* (1*938); and in the delimitation of orders * of the Pyrenomycetes by Miller (1949) and Luttrell (1951). Ostiole (sing, ostiolum) It is.a mouth or opening, more specifically, the sehizogenously formed canal in the tip of a true perithecium, lined with periphyses; as defined by Miller (1928). Paraphvses (sing, paraphysis) - These are sterile hyphal threads which remain intermingled with unitunicate asci, having the free ends'converging toward the ostioles. They may be filiform or.slender, simple or branched, septate or aseptate and may be absent or gelatinized at maturity. Paraphvsoids (sing, paraphysoid) - These are threacl- like elements of the remains of the interthecial stroma having cellular structure and being without free ends, but continuing into the pseudoparenchymatous tissue. The para- physoids remain associated with bitunicate asci. Periphyses (sing, periphysis) - These are fine hyphal elements having free apices. They line the ostiolar canal of the perithecium.

18 » I % 18 - t Hairs (sing, hair) - The fruit bodies of the Pyreno- mycetes are usually smooth but cornetirfes with hairs on them. i * The hairs may be thin- to thick-walled, hyaline to"deeply coloured, septate to asept*ate.. The character of hairs is # used in the separation of genera e.g. Herpotrichia. Appendages (sing, appendage) - The fruit bodies of s«me members of the Pyrenomycetes are append*aged..the appendages may be simple or branched, septate or aseptate, usually coloured. The presence or absence and the nature of appendages are taxonomic characters for the delimitation of genera and species of the Pyrenomycetes e.g. Appendlculdlia, Gnomonia. ', Setae (sing, seta) - Other than hairs and appendages, the perithecial wall may* bear certain stiff, pointed to hooked outgrowths - setae. Ascus (pi. asci), It is a sac-like structure in which the ascospores are formed endogenously by karyogamy and meiosis. Asci of the Pyrenomycetes are variously shape: globose, oblong, elliptical, clavate and cylindrical. They may be short-or long-stalked. The ascus wall may be composed of single layer or of 2 layers i.e. unitunicate or bitunicate. The mature asci are usually 8-spored, but sometimes may be 2-, 3-, 4- and many - spored. In some cases tfie ascospores may bud off secondary spores or conidia still within the ascus as in the genus Thvronectria.

19 I 19 - The wall of unitunicate asci may be uniform in thickness but more often with conspicuously thickened at uhe apex. The unitunicate a^ci are thin-wallted and* the ascospores are discharged through* an apioal pore which otherwise remains. closed by a plug*. The ascus wali or any part of it turns blue with Melzer's reagent. The ascus wall may be persistent or evanescent. The unitunicate asci are usiially long-stalked. * The stalks of asci may be evanescent as -in the genus Gnoaonia. The bitunicate asci consist of a rigid outer and an extensible inner wall. At maturity the outer wall ruptures at the apex and the inner wall expands to form a.long cylin- drical sac and the ascospores escape, through the pore at the apex. The ascus wall or any part of it does not turn blue with Melzer's reagent. The ascus wall is not uniform in thickness and is usually thickened at the apex. The structure of asci serves an important taxsy^omic character. It was used as a key character in the, separation of Mycosphaerellaceae;t Pleosporaceae, and Massariaceae from the Gnomoniaceae and Clypeosphaeriaceae by Lindau (1897); in the separation of genera in the Sordariaceae by Griffiths (1901); in the delimitation of orders of the Pyrenomycetes by Nannfeldt (1932) and Miller (1949); and In the delimitation of series by Luttrell (1951). Ascospores (sing, ascopore) - They vary greatly in size, shape and colour. They may be aseptate or septate. The

20 l 20 i septation may be transverse or both longitudinal and transverse. The wall may be Smofith or. variously ornamented. The ornamentation may be in the form of longitudinal striation, spine, reticulation, or warts. The* spares may be hyaline to coloured, eguttulate to gut'tulate, with or without appendages. COLLECTION AND PRESERVATION OF SPECIMENS With a view to study the Pyrenomycetes in their natural habitat and to collect them for detailed study in the laboratory, frequent collection trips were undertaken in different parts of West Bengal (both plains and. hills) during different seasons throughout the year from 1965 to The areas of * field study and collection covered the districts: 24-Parganas (including localities in #nd around Calcutta), Howrah, Hooghly, Midnapore, Burdwan, Purulia, Nadia, Murshidabad, Maldah, West Dinajpur, Cooch Behar, Jalpaiguri (including forest ^ areas), Darjeeling (including Siliguri at an altitude ranging * from 23-1,000 ft. mainly forest areas, hills of Kalimpong, Kurseong and Darjeeling at an altitude ranging from 3,000-8,000 ft. including forest areas). The fungi of this group were found to occur mostly in all seasons of the year but a few were found to appear only in a particular season of the year. The fungi belonging to the Microthyriaceae, Asterinaceae, and Meliolaceae were found to occur during winter

21 I and spring seasons in plains but from Maj to July in hills, the fungi belonging to trie HypocrealeV and some Sphaeriales in rainy season and comparatively larger fungi, e.g. Hypoxylon. Xylaria. etc. i*n rainy and autumn seasons. Large number of pyreno'mycetous fungi of wide range of forms were collected and preserved. During collection in the field, a 10 x hand lens and a sharp knife were very useful for locating the fungi in natural habitat arid preliminary examination of fruit body in the collection spots. In the collection spots, the specimens were collected and examined by the hand lens. Then one or two fruit bodies were taken and crushed. Those fruit.bodies that easily cracked into small fragments, were rejected and those fruit. bodies having sticky contents were collected. The collected specimens were taken in -small brown paper bags or in card board boxes on which minimum field notes such as lo^lities; * date of collection; habitat; texture; external features and colour of fruit body.^ere recorded. When it was not possible to identify the host plant in the field, one or two twigs of that plant with inflorescences were collected and preserved for proper identification. Some of the specimens collected were preserved dry and others in liquid. For dry preservation, the hard specimens were allowed to dry in room temperature, but the fleshy specimens were placed in a drying oven at 50 C for three to four hours for five days. Specimens

22 i of leaf inhabiting fungi were dried by the usual pressing method used for.phanerogamic specimens#and placed in herbarium * packets. Tl^rodghly dried specimens were treated with Para- dichlorobenzene to*prevent*against destruction by insects. As to wet preservation, fleshy specimens were preserved in a liquid made out of 40 per cent formaldehyde with 5 per cent glycerin in 1 : 1 ratio. All specimens collected were labelled as PCG (Presidency College herbarium, Calcutta, India). MATERIAL AND METHODS The collected specimens were at first examined in the " laboratory with dissecting microscope at x and the external features and colour were recorded. In cases where the fungi were immersed in the host tissue, at first the host tissues were removed with a sharp knife and then examined under the microscope. Fresh specimens were studied from crush mounts in water, and from hand sections stained in lactophenol cotton blue. A fruit body or its content was placed in a drop of water on a slide, covered with a cover glass gently and examined. Then the nature of the wall of the fruit body, colour, shape and characters of asci and ascospores were examined and relevant data were collected. Observations were

23 23 also made from serial microtome sections#by fixing specimens in FAA for 12 hfs. followed by.dehydration in alcohol grades» and xylene series, embedding i'n paraffin wax, and sectioning at ju. The microtome 'sections were stained in lacto- phenol cotton bliie and safranin-fast green combination. The dried specimens were treated with 2% KQH for about five minutes and then washed in water before examining. After this treatment the specimens were softened and then sectioned with a good razor blade. The sections v;ere stained in lacto- phenol cotton blue, mounted in lactophenol and covered with cover glass and ringed with paraffin wax. In case of fungi belonging to Meliolaceae, Asterinaee^e and Microthyriaceae, at first a good colony was selected, one drop o.f colloidion- acetone was placed upon the colony. After drying it was removed. Its removal from the leaf usually brought the whole of the surface mycelium intact within it. The whole thing was then placed into laptophenol,.covered with cover glass and ringed with paraffin and was ready for examination. The * superficial mycelium of *the colony was also removed from the host by heating in lactophenol. For critical studies of ascospore ornamentations, the spores were stained using the technique laid down by Le Gal (1947) and Korf (1952). KOH-Phloxine staining and Sudan III staining technique were applied for the study of spore septation and for the

24 24 study of the nature of oil globules^resp ctively... 9 All microscopic examinations were made with Reichert t * compound microscopy of varying magnification range. Camera lucida drawings were made with -the aid* of standard camera lucida attachments.. Photography was done with Reichert camera by using biue filter. Photography of small si-ze specimens v^as done with reflected light. CLASSIFICATION OF PYRENOMYCETES [based on Nannfeldt (1932) and modified by Miller (1949), Luttrell (1951, 1955), von Arx and Muller.(1954), Munk (1957), Muller and von Arx (1962) and Dennis (1968)J A key to the Drders, Families and Genera I. Asci borne in perithecia which may be separate or grouped., or immersed in a stroma. Asci unitunicate, often becoming mucilagfnous early, ylightly thickened at the tip; paraphyses and periphyses often present... Euascomycetidae... A II. Asci borne in locules in stromata, which, when uniloculate may resemble perithecia. Asci bitunicate, thickened at the apex; paraphyses and periphyses usually lacking; paraphysoids usually present Loculoascomycetidae.. D

25 25 - v A. Peritheeia opening with a roundish canal covered with pefiphyses,. bright, or dart; no mycelial * appendages or setae ' i B. Peritheeia an<f stromata, if present,... B dark*, membranous or carbonous... C C. Ascal bases not gelatinizing, mature asci remaining attached to the inner perithecial' wall *... Sphaeriales CC. Ascal bases gelatinizing, mature asci loose in perithecial cavity. and extruded though.the opening... Diaporthales (Single family Diaporthaceae) BB. Peritheeia and stromata, if present, bright coloured, soft, fleshy, or ^ waxy.... Hypocreales # (Single family Hypocreaceae) AA. Peritheeia remaining closed for very long, ostiolate at maturity; mycelial appendages or setae usually present... Meliolales D. Asci claviform or almost spherical, in which case distinctly stalked, occasionally also almost cylindrical. Fruit body at

26 f maturity mostly opening wide* opening by split or tear or poire, occasionally also becoming mucilaginous %... Dothio^ales DD. Asci* ellipsoid or oval or cylindrical or narrow claviform; fruit body mostly with apical papilla, opening in the* apex with a roundish pore or canal *.. Pseudosphaeriales SPHAERIALES A. Perithecia nonstromatic, superficial or immersed in substratum B. Ascospores dark, often appendaged, unicellular.... Sordariaceae (Single genus Pleurage treated here) BB. Ascospores hyaline, without any appendage, «not unicellular... Sphaeriaceae * AA. Perithecia stromatic G C. Perithecia clypeate... Phyllachoraceae (Single genus Phyllachora treated here) CG. Perithecia not clypeate... D D. Stroma consisting of both host and fungal tissue... Diatrypaceae. DD. Stroma entirely fungal E

27 i E. Spores dark brown to black, always * unicellular, elongate germ silt present... Xylariaceae i EE. Spores hysfline to yell.owishf always *2-celled^ cells not equal in size, no elongate germ slit formed... Amphisphaeriaceae (Single genus Apiospora treated here) MELIOLALES A. Ascocarp not becoming gelatinous above at maturity... Meliolaceae AA. Asci exposed by gelatinization of upper portion of ascocarp *... Englemlaceae. (not treated here) DOTHIORALES A. Spores uni- to multi-cellular; fruit body nqt attached with free mycelium... Dothioraceae AA. Spores 2-celled; fruit body attached with free mycelium... Asterinaceae PSEUDOPHAERIALES A. Fruit body flat, crustaceous, shield-shaped, dimidiate... Microthyriaceae (Single genus Asterinella treated here)

28 28 AA. Fruit body not flat or dimidiate, bu1i spherical, hemispherical r condcal. * * *... Pleosporaceae % SPHAERIAGEAE A. Perithecia with long* beak and immersed except the small portion of the beak... Ceratosphaeria AA. Perithecia without beak, superficial or only basal portion immersed... Zjgnoella DIATRYPACEAE A. Ascospores brown to dark brown.... Anthostoma AA. Ascospores not brown B B. Stroma cushion-like, erumpent C C. Asci 8-spored D D. Perithecia not beaked and separately erumpent #*... Diatrvpe DD. Perithecia beaked and collectively erumpent... Eutypella CC. Asci many-spored... Diatrypella BB. Stroma usually embedded in the host tissue or rudimentary... Eutypa

29 XYLARIACEAE \ *, A. Perithecia separate in individual stroma, sometimes # with a hypostroma... Rosellinia AA. Perithecia several in a stroma « B B. Stroma effused, pulvinate or globose, sessile C C. Internal zonation present.... Daldinia * GC. No internal zonation... Hyp ox vl on BB. Stroma stalked, clavate to cylindrical... Xyljaria DIAPORTHACEAE A. Spores brown at maturity; stromatic... B B. Spores 1-septate, elliptical *... Valsaria «BB. Spores multisepiate, cylindrical *... Melogramma AA. Spores hyaline; non-stromatic... Gnomonia HYPOCREACEAE A. Perithecia immersed singly or in groups in stroma B

30 B. Spores breaking down into «onst?tuent cells ft in the ascus itself, hy.alin^ l... Hypocrea BB. Spores not breaking down into* constituent cells, brown... Valsonectria AA. Perithecia not immersed in the stroma, sometimes seated on a stromatic base, or on & subiculum... C ft C. Spores 1-septate... Nectria GG. Spores muriform... Thyronectria MELIOLACEAE A. Spores 2-celled... Armatella AA. Spores more than 2-celled B ' * B. Mycelial setae present *... Meliola BB. Mycelial setae absent G G. Perithecia with setae * I.. Irenopsis CC. Perithecia *with "larviform" appendages... Appendiculella CGG. Perithecia with neither setae nor appendage... Asteridiella DOTHIORACEAE A. Stromata superficial, freely situated on the substratum Myiocopron

31 AA. Stromata erumpent... #.:.... B * B. Asci situated on* dome-^haped^basal cells of the locales, no paraphysoids present... Phvllachorella BB. Asci not* situated on dome-shaped basal cells of the locules, paraphysoids present... Botrygsphaeria ASTERINACEAE A. Mycelial conidia absent... Asterina AA. Mycelial conidia present.. Clypeolella * 0 PLEOSPORACEAE A. Spores unicellular, brojrn t *... Astrocystis AA. Spores multicellular,* hyaline or brown... B B. Spores with both transverse or longitudinal septa, always bijown... Pleospora BB. Spores only wi.th transverse septa... G C. Spores surrounded by mucilaginous sheath... Massarina GC. Spores not surrounded by mucilaginous sheath D. Fruit body large, multiloculate; hypostroma present; spores always uniseptate E

32 32 E. Septum at orie eijd; spores brown 9 EE^. Septum never at one end; spores * hyaline... Microsyclus DD. Fruit body small, uniloeulate; hypostroma absent; spores 1- to multi-septate... F F. Fruit body superficial and» attached with loose hyphae.. Herpotrichia FF. Fruit body immersed and no superficial hyphae attached (often hyphae are present but not obvious as in Herpotrichia) *,... Leptosphaeria * DESCRIPTION OF TAXA I #.. SORDARIACEAE t PLEURAGE Fr. sensu Cl. Moreau Encyclopedie mycologique 26: Synonymy : Schizothecium Corda, leones Fung. 2 : Not Schizotheca Ehrenb Podospora Cesati, Rabenh. Herb. My«ol. no Philocopra Speg., Anales Soc. Sci. Argent

33 Type species : Pleurage curvula. (Be*Bary) Kuntze.,. * * Peritheeia scattered or aggregated, superficial or % sunken, membranaceous or aorihceous, without stroma, pyriform, «* no sharp boundary between body and ostiole; asci without functional internal membrane or apical perforation, stretching at maturity; paraphyses ventricose or filjfform-tubular, usually longer than the asci; ascospores* usually biseriate or in a cluster, clavate or cylindrical when young, mature spore oval or ellipsoid, dark-coloured, with a germ pore near the distal end, with or without primary appendages, but always 0 attach to them two or more hyaline gelatinous secondary appendages of variable length. The genus Pleurage was erected by Pries (1849) and later thoroughly studied *and extended by Moreau (1953). There was great controversy regarding the nomenclatural status of the genus Pleurage. Corda (1835) described the genus ^ I Schizotheeium (not to be confounded with Schizothecium Fenzl * 1833). Fries 1849 with at confusion between Schizothecium Corda and Schizotheca Ehrenberg, created the genus Pleurage by indicating the type of the genus Schizothecium fimicolum Corda. The genus Podospora. with type Pj. fimicola was erected by Cesati (1856) including fungi having spores with primary and secondary appendages, which is no^other than that of Schizothecium fimicolum (Griffiths, 1901; Moreau,

34 J Jig 1. PTeurage aracnoidea var. jjlabra^. k. B. Section through the peritheciurc, Young ascus showing the arrangement ascospores, x 550. D. Mature ascus, Mature ascospores, x 550. Habit, x 5. x 180. C. of young x 550i E.F.

35 ). Different authors accepted the name Podospora, though the description* gi,ven hy Cesatl is less clear than that by. * Fries concerning the genus Pleurage. because the earlier *. ± PIeurage has no Latin description, from that point Podospora is more confirmed in nomenclature. But Griffiths (1991), Moreau (1953) accepted the genus Pleurage as this is earlier than Podospora. Some authors (e.g. Cain and others) placed PIeurage in Sordiaria: others (e.g. Kirschsteh and others) united Pleurage and Bombardia under the genus Bombardia. On the other hand some mycologists placed a part of secies of Pleurage having 8-spored asci, undes the name Philocopra. According to Moreau (1953) this division has no basis and the genus Pleurage should be treated as a separate genus. Kc r & Llaity Pleurage arachnoidea (Niessl) Gri*ff. var. glabrayvar. nov. provisorum. «(Fig. 1) Perithecia numerous, scattered or densely gregarious, partly immersed, darkbrown to black, coriaceous, glabrous, subglobose to pyriform, p in diameter, ostiole inconspicuous; in section, the lateral wall p thick and composed of two regions: the outer made up of small round to globose thick-walled cells, 3-5 p in diameter and the inner layer forming the greater part of the wall, made up of

36 large thin-walled elongated to polygonal cells, x 3-4 p, which merge fwith the thin-walled compressed cells that line the perithecdal cavity; ajci many, arising from both sides and bases of the perithecia, 8-spored, short-stalked, unitunicate, (p. sp ) x p and intermingled with filiform septate, hyaline paraphyses; ascospores coiled and wor^-like.when young, elliptic-cylindrical at maturity; primary appendage at the lower-end, large hyaline cylindrical, aseptate, straight to curved, x 4-5 p and occasionally smaller at the upper; brown to brownish black, x p; primary appendages^ith a number of small gelatinous secondary appendages. Etymology - From the pature of peritfiecia*. Habitat - On cow dung Type locality - Palmajua (7,225 ft.), Darjeeling,West Bengal, India. % Type specimen studied - PCC *1504 (=IMI ), Leg, M. K.Maity, June 18, Note : This specimen is very close to Pleurage archnoidea (Schw.) Seeler, but does not possess setae on the perithecia. So it has been proposed as a new variety of P. arachnoidea.

37 Fis;. 2. Ceratosphaeria ervatamiicola. A, Habit, x 20. B. Section of perithecium, x 120. C. Ascus, x D. Ascospores, x