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Pollen grain morphology of Bromeliaceae species collected in areas of the Atlantic Rainforest of southeastern Brazil was studied. The following species were analyzed: Aechmea bambusoides, T. stricta Sol., T. gardneri Lindl., T. geminifl ora Brongn. and Vriesea grandifl ora Leme. Light and scanning electron microscopy were used and the species were grouped into three pollen types, organized according to aperture characteristics: Type I -pantoporate pollen grains observed in P. petropolitana, Type II -2-porate pollen grains, observed in the genera Ananas, Aechmea and Quesnelia, and Type III -1-colpate pollen grains, observed in the genera Billbergia, Pitcairnia, Tillandsia and Vriesea. Pollen data led to the construction of an identifi cation key. The results showed that the species analyzed can be distinguished using mainly aperture features and exine ornamentation, and that these characteristics may assist in taxonomic studies of the family.

The spore morphology of 25 taxa belonging to the family Dicranaceae, including 11 genera is described. The majority of the spores do not exceed 25 mm in the largest diameter. Three spore types, characterized by their surface ornamentation, are established, reflecting the species taxonomic relationships. The genera Anisothecium, Atractylocarpus, Bryohumbertia, Campylopus, Holomitrium, Oreoweisia, Pilopogon and Thysanomitrium present a surface recovered by elements resembling granules, they are included in the granuloid type. The piloid type in Dicranella and Microdus it is characterized by a surface with pilum-like elements. The insuloid type is restricted to the genus Campylopodium. The spores are resistant to the acetolysis mixture; the sclerine maintains its integrity when submitted to this method; only the intine is lost. The family Dicranaceae belongs to the order Bryales. This years (Sorsa & Koponen 1973, Hirohama 1976, 1977Olesen & Mogensen 1978, Stefureac et al. 1979, Mogensen 1981, moss family was described by Schimper (Bruch et al. 1983, Brown & Lemmon 1980, 1984a, b, 1988, 1991 Boros 1836 Boros -1855 Oreoweisia, Pilopogon and Thysanomitrium were studied in The recognition of the subfamily Trematodontoideae, order to evaluate spore morphology can provide additional including the genera Bruchia, Trematodon and Wilsoniella characters of importance for circumscribing the family. was questioned by Buck (1979). He proposed the reevaluation of the family Bruchiaceae in order to include the genera Bruchia, Trematodon, Pringleella and Eobruchia based on the presence of the long-necked and stomatose MATERIALS AND METHODS capsules. The genus Wilsoniella was included in the family Ditrichaceae. AndréaThe spore morphology of 25 taxa, belonging to 11 genera of the family Dicranaceae was studied. The material was collected in Brazil Vitt (1984) presented the family Dicranaceae with 55 and, is preserved in Brazilian herbaria (MG, PACA, R, RB, SP). genera, including Bruchia, Eobruchia and Trematodon. TheThe spores were prepared untreated with glycerin-jelly on microscope genera Pringleella and Wilsoniella were transferred to the slides or using the acetolysis method (Erdtman 1952). Measurements family Ditrichaceae. Mü ller & Frahm (1987) and Frahm of the shortest and the largest diameters (in polar view) and the (1991) adopted the subdivision in subfamilies with some polar axis and the equatorial diameter (in equatorial view) were alterations. made in 25 randomly selected spores. Mean, standard deviation, standard error, and the range were established. Sclerine thickness,The family Dicranaceae has a large geographic distribuas well as the largest length of the apertural region, was based on tion, with species that occur in the arctic, antarctic, temper-10 measurements, and only the mean is presented. The first exsiccate ate, tropical and subtropical areas (Sehnem 1953, Frahm listed under the ''Specimens Examined'' is termed the reference 1991), and growing on various substrates, such as rocks, specimen and the oth...

-(Spore morphology of Polytrichaceae Schwägr. (Bryophyta) from Brazil). Spore morphology is described for all six genera of Brazilian Polytrichaceae based on light and scanning electron microscopy study of 13 species of the approximately 30 species of the family native to the country. Discussion on its taxonomic importance is also provided. Spores were analyzed before and after the acetolysis method. Polytrichaceae is eurypalynous. The spore surface of Atrichum androgynum (Müll. Hal.) A. Jaeger has regular granules and isolated gemmae. The spores of Itatiella P. Beauv. and Oligotrichum Lam. & DC. species are small to medium size, with bacula, elongated processes, clavae and pila on the surface. Species of Pogonatum P. Beauv. gathers spores of very small to small size, granulate surface. Polytrichadelphus pseudopolytrichum (Raddi) G. L. Sm. spores are very small to small size, and ornamentation formed by reduced smooth spines. In Polytrichum Hedw. species the spores are small and ornamentation is formed by ornamented spine-like processes to granules.

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-(Spores morphology from Sematophyllaceae Broth. from three fragments of Mata Atlântica, in Rio de Janeiro, Brazil). In the present work the spores of seven species of the family Sematophyllaceae Broth. (Bryophyta) from three areas of Mata Atlântica were analyzed. For the spores' external morphology analysis, the direct method in glycerined gelatin was used and for the measurements the method of acetolysis was used. The largest and smaller diameters (in polar view) and the thickness of the wall were measured. The analysis was carried under optical microscope and scanning electronic microscope. The spores are isomorphic, from small to medium size, heteropolars, of subcircular amb, with proximal apertural region and granulated surface. The apertural region is irregular. The variations found between the spores of the different species are related to the size of the spores and the distribution of the trimming elements.Key words -Bryophyta, Mata Atlântica, Sematophyllaceae, spores RESUMO -(Morfologia dos esporos de Sematophyllaceae Broth. ocorrentes em três fragmentos de Mata Atlântica, no Rio de Janeiro, Brasil). No presente trabalho foram analisados os esporos de sete espécies da família Sematophyllaceae Broth. (Bryophyta) ocorrentes em três áreas de Mata Atlântica. Para análise da morfologia externa dos esporos, utilizou-se o método direto em gelatina glicerinada e para as medidas foi utilizado o método de acetólise. Foram medidos os diâmetros maior e menor (em vista polar) e a espessura da parede. As análises foram realizadas sob microscópio de luz e microscópio eletrônico de varredura. Após a realização das medidas, realizou-se a análise estatística e estas foram apresentadas em tabelas. Os esporos são isomórficos, de tamanho pequeno a médio, heteropolares, de amb subcircular, com região apertural proximal e superfície granulada. A região apertural é irregular. As variações encontradas entre os esporos das diferentes espécies estão relacionadas ao tamanho dos esporos e à distribuição dos elementos de ornamentação.Palavras-chave -Bryophyta, esporos, Mata Atlântica, Sematophyllaceae

In bryophytes, establishment can occur by a sexual or asexual process, but the production of spores enables colonization of a wider range of habitats and substrates than can asexual propagules. Successful germination is critical for establishment in a new environment. Th is paper addresses germination and sporeling development in Frullania ericoides, a leafy liverwort species. Fresh spores were inoculated in vitro in diff erent culture strengths of Knop's nutrient solution (one-fourth strength, half strength, full strength, one and a half strength and double strength), in order to evaluate the eff ects of this solution on spore germination and on the development of external protonema. On the fi rst assessment, spore germination was observed at all the concentrations. Germination was endosporic, with cell division and proliferation, resulting in a globular protonema, within the spore wall. Beginning at the fourth week, the development of tightly concave primordial leaves was observed in all but the double-strength medium. Th roughout the period of study, the treatments with lower concentrations exhibited external protonema with greater lengths. Th e double-strength treatment was statistically diff erent from other treatments in at least two parameters. Th e results of this study demonstrate the potential of in vitro culture techniques for bryophyte spore studies and germplasm preservation.