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Poroleprieuria gen. nov. is described and illustrated to accommodate P. rogersii in the Xylariaceae, Xylariales. This ascomycete, known only from the type collection, is characterized by reniform, light brown, smooth ascospores with a germ pore; cylindrical, persistent asci lacking an apical apparatus, septate persistent paraphyses, and erumpent, erect, dark brown, fragile, subcylindrical stromata. The characteristics of this xylariaceous fungus were compared with those of some other ascomycetes having superficially similar cylindrical stromata or ascospores with germ pores.

The perithecial ascomycete Ophiodothella vaccinii causes a leafspot disease of sparkleberry (Vac- cinium arboreum), in which an anamorph is produced early in the life cycle of the fungus. The anamorph forms shiny, black, pulvinate conidiomata that con- tain a single central pore. After initial infection, fun- gal hyphae permeate the interior tissues of the leaf, creating lesions. Conidiomata are initiated by the for- mation of a small layer of intertwined, thicker-walled hyphae beneath the epidermis of the lesion. Near the center of this hyphal layer a subglobose collection of thick-walled hyphae is formed. This hyphal collection grows upward, becoming conical and pressing against the epidermis. Elongation of a columnar apex of the hyphal collection ruptures the epidermis, creating a pore. Subsequent expansion and development of co- nidiophores and conidia push the epidermis upward, lifting it away from the column, opening the pore and allowing conidia to emerge. The conidioma is regarded as a modified acervulus.

This is the first ultrastructural study of as- cosporogenesis in Melanospora with deliquescing asci. Electron-opaque vesicles found in the ascogonial cell and the young ascus were involved in the formation of a double-membrane envelope just inside the ascus plasmalemma. The apparent origin of the ascospore- delimiting membrane is described using chemically fixed material. This alternative theory of double- membrane envelope formation as demonstrated in M. zamiae will be worthy of testing in other ascomy- cetes, especially in those shown to have the electron- opaque vesicles. The mature ascospores of M. zamiae were enveloped by two distinctive thick walls, which in fact comprised multiple layers of wall material. Due to the fast process of ascospore maturation, and the difficulties encountered during fixation of such thick-walled spores, the origins of ascospore wall ma- terials in M. zamiae remain unresolved.

A detailed study of ascomal morphology and development in Cercophora palmicola showed that ontogeny is ascohymeniaceous, giving rise to an ostiolate perithecium. Ascomal initials consist of a coiled ascogonium surrounded by several layers of hyphae whose cells become pseudoparenchymatous. The centrum of the young ascoma is composed of a few rows of large, thin-walled pseudoparenchymatous cells that line the ascomal wall, with the central region filled by tightly packed, filamentous paraphyses. The ascogenous system forms along the inside of the layer of pseudoparenchymatous cells at the base of the paraphyses and gives rise to unitunicate asci that grow up among the paraphyses. The wall of the mature perithecium is greatly thickened. It is composed of three regions: a thin outer region of darkly pigmented, angular cells with thickened walls; a broad central region of cells with gelatinized walls; and a thin inner region of flattened cells. Ascomal ontogeny in C. palmicola conforms well to the Sordaria type of development, as defined by Huang. Cercophora palmicolaHanlin & Tortolero is a sordariaceous perithecial ascomycete that occurs on palm stems in the tropics. It possesses several unusual morphological features that were noted in the original description (Hanlin and Tortolero, 1987), but which were not described in detail. The purpose of this paper is to provide additional information on the morphology of C. palmicola and to compare it with information published on related species.

The 30 taxa sampled for this study were chosen based on their taxonomic position or partic- ular morphological characters, which are related to those of Chaetomium. The 15 fungal isolates se- quenced herein were obtained during a fungal bio- diversity survey of tropical soils or from the collec- tions of R.T. Hanlin. Fifteen species were selected from the published data. The aligned sequences of the 5' portion of the 18S ribosomal DNA were ana- lyzed to infer the phylogenetic relationships among Chaetomium and related genera. The sequence data confirmed the generic entity of Achaetomium and placed Ascotricha within the Xylariaceae. The analyses also defined the monophyletic lineage of the Mi- croascaceae and the evolutionary linkages between the families Sordariaceae and Chaetomiaceae. The placement of Coniochaeta in the Coniochaetaceae and Chaetomium and Achaetomium in the Chaetomi- aceae, under the order Sordariales, is supported by

Phylogenetic analyses of partial sequences (1002 basepairs) from the nuclear encoded small subunit ribosomal RNA (18S rRNA) were performed to determine the phylogenetic relationships of the ascostromatic fungi, Botryosphaeria, Guignardia, Leptosphaerulina, Didymella, Venturia, Sporormia , and Sporormiella. Our studies confirm the concept that the subclass Loculoascomycetidae is paraphyletic if Chaetothyriales is included, as this order and the plectomycetes constitute a monophyletic clade that is highly supported in our and some previous phylogenetic analyses. In general, taxa that lack pseudoparaphyses (Dothideales) or have reduced hamathecial tissue, such as Botryosphaeria and Guignardia (sensu Sivanesan), are a sister group to the Pleosporales, the most derived group, whose members have pseudoparaphyses. The two species of Leptosphaerulina , which also lack pseudoparaphyses, clustered within the Pleosporales, rather than within the Dothideales, with high confidence from bootstrap values. Didymella nested within the Pleosporales with a high degree of confidence, and is the sister group to Leptosphaerulina. The taxonomic placement of Venturia and Sporormiella corresponds to the Pleosporales.

Myriogenospora atramentosa produces partial to complete sterility of host grasses. Geographical and host species distributions were assessed and updated. It is reported only from the New World and appears to be limited to the highly evolved grass tribes Andropogoneae and Paniceae. Included in these tribes are the previously unreported host species Panicum scoparium, Paspalum urvillei, Erianthus brevibarbis, E. contortus, E. giganteus , and hybrids from crosses with Erianthus spp. Additionally, M. atramentosa is reported for the first time growing on Paspalum notatum (bahiagrass), and Panicum hemitomon in South Carolina, U.S.A. Sequence data (ITS regions 1 and 2 and 5·8S rDNA) from several isolates indicated that there is a significant level of DNA sequence differentiation between isolates of M. atramentosa , which suggests that there are at least two distinct sequence groups, or cryptic species, within the currently defined morphological species.

In Melanospora zamiae a total of five nuclear divisions took place during ascosporogenesis. The first and second divisions were meiotic in which the single diploid nucleus divided into four haploid nuclei. The mitosis that followed gave rise to eight nuclei which characteristically assumed a 1:4:3 (apical:middle:basal) spacing in the clavate ascus. After ascospore delimitation, each nucleus in the young ascospore underwent two successive mitoses producing four haploid nuclei in each spore. Equatorial arrangement of these nuclei was observed in the mature ascospores.

An apothecial discomycete from diseased branches of Japanese red pine in Georgia was found to be conspecific with Cenangium atropurpureum. After comparison of the Georgia material with Ce. ferruginosum, the type species, it was concluded that on the basis of ectal excipular characteristics, Ce. atropurpureum is better accommodated in Crumenulopsis. This species differs from European species of Crumenulopsis in the oval shape of the ascospore, presence of a gelatinous ascospore sheath, and possession of a diffusible purplish pigment in KOH. It differs from the Florida species, Cr. lacrimiformia, in the shape of the ascospore and ascospore sheath, larger size of the ascoma, presence of the purple pigment, and host species.

Cultures of Leptosphaerulina crassiasca from single ascospores formed ascostromata, indicating that the fungus is homothallic. Mycelial hyphae were septate, with uninucleate cells, and they gave ri...

Periconia variicolor was isolated from water of an evaporation pond used for salt production on the southwestern coast of Puerto Rico. On the basis of cultural and morphological characteristics and ITS sequence it is describe as a new species of Periconia.

Acremonium is generally considered to be a highly polyphyletic form genus containing distantly related fungi. Sectional divisions within Acremonium distinguish the clavicipitaceous grass endophytes of sect. Albolanosa from the generally saprobic species of sections Acremonium, Chaetomioides, Gliomastix, and Nectrioidea. In an effort to assess the possible number of lineages currently placed within Acremon- ium and to determine which groups of sexual asco- mycetes are phylogenetically affiliated with Acremon- ium species, maximum parsimony and neighborjoin- ing analyses were performed using partial sequences of the nuclear small subunit ribosomal DNA (18S rDNA). Acremonium was shown to be a polyphyletic taon with affiliations to at least three ascomycetous orders: 1) most of the examined species from the sections Acremonium, Gliomastix, and Nectrioidea showed a relationship to the Hypocreaceae even though many of these species have never been asso- ciated with any teleomorph; 2) the grass endophytes of sect. Albolanosa and other taxa from the Clavicip- itaceae formed a monophyletic group derived from within the Hypocreales; 3) the thermophilic A. ala- bamense of sect. Chaetomioides was derived from with- in the Sordariales. Acremonium alternatum, the tye species of the genus, was one of the species showing affiliation to the Hypocreaceae. In order to eliminate some of the heterogeneity within Acremonium while also emphasizing the unique biological, morpholog- ical, and ecological characteristics of the grass en do

We describe a perithecial, pleomorphic ascomycetous fungus from the Early Devonian (400 mya) Rhynie chert; the fungus occurs in the cortex just beneath the epidermis of aerial stems and rhizomes of the vascular plant Asteroxylon. Perithecia are nearly spherical with a short, ostiolate neck that extends into a substomatal chamber of the host plant; periphyses line the inner surface of the ostiole. The ascocarp wall is multilayered and formed of septate hyphae; extending from the inner surface are elongate asci interspersed with delicate paraphyses. Asci appear to be unitunicate and contain up to 16 smooth, uniseriate-biseriate ascospores. The method of ascospore liberation is unknown; however, the tip of the ascus is characterized by a narrow, slightly elevated circular collar. Ascospores appear 1-5 celled, and germination is from one end of the spore. Also present along the stems and interspersed among the perithecia are acervuli of conidiophores that are interpreted as the anamorph of the fungus. Conidiogenesis is thallic, basipetal and probably of the holoarthric-type; arthrospores are cube-shaped. Some perithecia contain mycoparasites in the form of hyphae and thick-walled spores of various sizes. The structure and morphology of the fossil fungus is compared with modern ascomycetes that produce perithecial ascocarps, and characters that define the fungus are considered in the context of ascomycete phylogeny.

A new genus is described to accommodate a species isolated from bat dung. This fungus forms a membranous ascoma with a long neck that is or- namented with lateral glandular hairs and terminal aglandular hairs; filamentous, septate paraphyses and deliquescent asci with hyaline, unicellular ascospores are formed in the base of the centrum. In order to analyze the systematic position of this ascomycete, its morphological characters and 18S rDNA sequences were studied and compared with superficially similar species. Based on morphological and phylogenetic analysis of 18S rDNA sequences, this fungus belongs in the Sordariales and is close to but separate from Chaetomium. The hyaline ascospores, without a germ pore, and the possession of an ascoma with a long neck ornamented with lateral glandular hairs is in contrast to other genera of the Chaetomiaceae. For these reasons, the new genus Guanomyces is proposed to accommodate the new species G. polythrix in the Chaetomiaceae of the Sordariales.

The family Hyaloscyphaceae includes saprobic species of the order Helotiales characterized by well differentiated hairs on the apothecium and an ectal excipulum of textura prismatica. Because of th...

Isolates of Diaporthe phaseolorum varieties caulivora, meridionalis and sojae, and Phomopsis lon- gicolla were grown on various substrates in the labo? ratory and inoculated into soybean plants in the greenhouse. Isolates varied in their ability to produce pycnidia and/or perithecia in culture. Both a and (3 conidia were observed in isolates of varieties cauli? vora and sojae, whereas only a conidia were observed in isolates of variety meridionalis. Stroma morphology and perithecial arrangement in stromata varied con- siderably in isolates of varieties caulivora and meri? dionalis, depending on the substrate. Some isolates of variety caulivora formed perithecia in a valsoid ar? rangement on potato dextrose agar and single peri? thecia in a well developed, immersed stroma in in? oculated soybean stems. Isolates of variety sojae always formed pustulate stromata and clustered perithecia. Nine quantitative morphological characters were ex? amined using two different cluster analysis methods and canonical discriminant analysis. The length and width of ascospores and asci and apical width of the perithecial beaks were stable across different sub? strates and resolved the isolates into three distinct

Capronia hystrioides sp. nov. (anamorph Phaeoramularia hachijoensis) was isolated from cherry fruit. Also isolated were Sporormiella subticinensis comb. nov., Leptodiscella africana, and Cladosporium malorum, a synonym of C. porophorum.

the fungus was observed on pods still attached to otherwise healthy trees. Aside from being blackish the pods did not show any trace of the symptoms of Monilia disease or black-pod disease and did not show any cells identifiable as Botryodiplodia theobromae Pat. Only the dead fallen pods often showed other fungi and eventually mosses. In one of the fallen pods the accompanying fungi were white, corticioid Basidiomycetes with clamp connections and acute, thin-walled incrusted hyphal ends. Spores were not recovered. The observations in Costa Rica suggest that Mycena theobromicola may be pathogenic, causing pod rot that might well have been misidentified as black-pod disease in the past and caused by the primary mycelium of the agaric. However, the available observations do not fully prove the point. Additional experimental work is required and should be carried out inasmuch as all local

Two hundred and twenty-three lyophilized isolates of fungi representing 91 species from sunflower seed were revived and grown in lipase medium with and without emulsified sunflower oil. Lip...

The structure of the hyphal septum in Spiniger meineckellus is of the dolipore type and is basically like that reported for other Holobasidiomycetes. The septum forms centripetally across the hypha and is accompanied by invagination of the plasmalemma. That portion of the septum surrounding the single central pore enlarges to form a septal swelling. The laminate central region of the septum wall extends through the septal swelling to the edge of the pore. On both sides of the septum there is a convex, laminate, electron-dense, perforate septal cap that covers the septal swelling and pore. The septal cap is sometimes continuous with endoplasmic reticulum that extends along the septum. Two electron-opaque rings surround the septal pore and rest on the shoulders of the septal swelling. Small, fine, dark filaments extend from these rings to narrow electron-dense bands inside the pore.

The isolation of Ascotricha xylina from sunflower (Helianthus annuus) oilseed grown in the U.S. is the first record of this fungus from sunflower seed and from the Western hemisphere. Examination of specimens of A. xylina from world herbaria confirmed the determination as A. xylina, and led to the discovery ofthe holotype that was lost for 33 years and the recognition of an isotype. The sizes of ascospores and widths of perithecial hairs from these specimens showed greater variation than described by Ames. Undescribed conidiogenous areas on perithecial hair apices were observed in culture. Centrum tissues appeared similar to other Ascotricha species, with broad, septate paraphyses interspersed among asci with non-amyloid apices.

An unusual powdery mildew found growing on cultivated and wild cotton (Gossypium barbadense, G. hirsutum, and G. purpurascens) in Lara State in western Venezuela has been identified as Brasiliomyces malachrae (Seaver) Boesewinkel. The fungus forms scattered colonies of white, superficial mycelium on the host leaves. Small, globose, hyaline, enclosed ascocarps are found on the surface of the mycelium. Each ascocarp contains three saccate asci; each ascus typically contains five oval, hyaline, one-celled ascospores, but 3-6 ascospores have also been observed. No appendages are present on the ascocarps. This is the first report of this fungus from Venezuela; it has previously been reported from Peru and Puerto Rico.

One hundred and fourteen species of fungi in 82 genera were identified from 2500 wood chips examined. Species of Trichoderma, Fusarium, Chaetomium, Aspergillus, Rhizopus and Graphium accounted for 48.6% of the isolates. None of the other species occurred in more than 5% of the wood chips. T. species accounted for nearly one-fifth of all colonies recorded. A. fumigatus was very common in both self-heated and ambient temperature piles. The possible threat to persons working around mulch piles from A. fumigatus is discussed. 29 references.

HANLIN, RIcHARD T. (Georgia Expt. Sta., Experiment.) Morphology of Neuronectria peziza. Amer. Jour. Bot. 50(1): 56-66. Illus. 1963.-Swollen tips of vegetative hyphae develop into multicellular, multinucleate ascogonia. Hyphae grow up to form a pseudoparenchymatous ascocarp wall. The ascogonia give rise to ascogenous cells from which croziers and asci form. As the ascocarp develops, an apical meristem produces many cells which are pushed downward and form a compact pseudoparenchyma in the centrum. As the asci form, the cells of the pseudoparenchyma elongate, forming central strands. These disintegrate as the asci grow up among them. Mature asci possess a thickened apical cap but no apical ring; the ascospores have longitudinal striations. The chromosome number is n = 5. The pattern of development resembles the Diaporthe type of Luttrell but is unique in the formation of strands from the pseudoparenchyma. Other characters, however, indicate a closer affinity to Nectria. NECTRIA PEZIZA (Tode ex Fries) Fries has long been considered a typical member of the genus Nectria. It was one of the original 18 species placed in the genus by Fries (1846-49), and has been retained there by most workers since. Seaver (1909a,b) considered it to be the type species of Nectria (sensu Seaver). In a study of Danish species of Nectria, Munk (1957) pointed out that there are 2 different types of centrum structure in members of the genus. One of these types, present in N. cinnabarina (Tode ex Fr.) Fr. and most other species studied by him, contained "apical paraphyses" (pseudoparaphyses) which descended from the apex of the ascocarp to its base. The second type of centrum, found in N. peziza, consisted of pseudoparenchyma, with pseudoparaphyses lacking. Correlated with centrum structure was ascospore ornamentation; species possessing pseudoparenchyma had longitudinally striate ascospores, whereas species with pseudoparaphyses had non-striate ascospores. Munk erected the new genus Neuronectria to accommodate those species having central pseudoparenchyma and striate ascospores. Neuronectria peziza (Tode ex Fr.) Munk (= Sphaeria peziza Tode ex Fr.) was designated as the type species. The genus Nectria was restricted to those forms having pseudoparaphyses and non-striate ascospores. A detailed study of ascocarp development in the type species, Neuronectria peziza, has been carried out and the results compared with previous studies in the genus Nectria. MATERIALS AND METHODS-The specimen used in this study was isolated from deer dung collected in Maine by Dr. L. E. Wehmeyer during the summer of 1959. Perithecia appeared after