The circumscription of the Agyriineae and the relationships of the genera and families included in it are evaluated. The anatomy and ontogeny of the genera Agyrium, Amylora, Anzina, Elixia, Lithographa, Miltidea, Orceolina, Placopsis, Placynthiella, Ptychographa, Rimularia, Trapeliopsis, Wadeana and Xylographa are investigated. Four families are accepted in the suborder: Agyriaceae, Anamylopsoraceae, Elixiaceae, and Schaereriaceae. The Rimulariaceae, Saccomorphaceae, and Trapeliaceae are included in the Agyriaceae. The Miltideaceae and the genus Wadeana, formerly included in the Agyriineae, are excluded from the suborder, and placed in the suborder Acarosporineae of the Lecanorales or incertae sedis, respectively. The systematic position of the Agyriineae is discussed and its position in the Lecanorales questioned. The new family Elixiaceae Lumbsch and the new genus Elixia Lumbsch are described. The genus Hafellnera is placed into synonymy with Schaereria. The new combinations Elixia flexella (Ach.) Lumbsch and Schaereria parasemella (Nyl.) Lumbsch are proposed.

  The lichenized ascomycete genus Xanthoria (Fr.) Th.Fr. (Teloschistaceae) in continental United States and Canada is revised. The following 15 species are recognized: Xanthoria borealis, X. candelaria, X. concinna, X. elegans, X. fallax, X. fulva, X. hasseana, X. mendozae, X. montana, X. oregana, X. parietina, X. polycarpa, X. sorediata, X. tenax, and X. ulophyllodes. The morphology, anatomy, secondary chemistry, ecology, and distribution of these species is discussed. A key for the identification of the species is presented together with distribution maps and illustrations of all species. Two taxa are described as new: Xanthoria montana and X. tenax. In addition to the newly described species, X. concinna and X. mendozae are reported for the first time from the study area. A number of taxa are reduced into synonymy and all names treated are typified.

  A new method to analyse optical activity of usnic and isousnic acids was established using high performance liquid chromatography with a chiral column. The method enabled analysis of these compounds even when their concentrations were low. Either (+)- or (-)-usnic acid was produced in most species examined here, but in the case of Flavocetraria lichens, both isomers were detected. (-)-Isousnic acid occurred together with (-)-usnic acid, and (+)-isousnic acid with (+)-usnic acid.

  The synthetic analogues of lichen compounds were prepared to compare with their anti-tyrosinase activities against those of intact lichen thalli. One of the synthetic analogues, 4-alkylresorcinols, showed strong activities.

  The tangled history of Anastrophyllum is reviewed and A. stellatum Schust. of Andean Venezuela is described and figured. This species fits best into subg. Schizophyllum, a subgenus in which gemma formation has not been before seen except in the Arctic A. sphenoloboides Schust. A. stellatum differs from the latter in the: (a) stellate gemmae, freely produced; (b) somewhat more asymmetric leaves with reduced dorsal lobes; (c) much coarser and more sharply defined, nodose trigones; (d) the dioecious inflorescences; (e) apparently uniformly intercalary branching. In size and aspect, leaf form, the development of pigmented 1-2-celled gemmae, and the weakly arched shoot apices approaching A. minutum, which is sometimes segregated in a genus Sphenolobus, yet the leaf cells, with coarsely nodose trigones, and the strongly corticated stem, are both suggestive of Anastrophyllum s. str.

  Fissidens luisierii was described by Potier de la Yarde in 1955 from the Azores. But no study of this species has been made since the original description. This species is compared and contrasted with F. adianthoides Hedw., the Asiatic F. nobilis Griff., F. polyphyllus Wits. ex B. S. G., and F. serrulatus Brid. A descripton of F. luisierii and illustrations of F. luiseirii, and F. serrulatus are provided.

  Leiomela (Bartramiaceae), is a new genus for Argentinian moss flora. Leiomela bartramioides (Hook.) Par. is recorded for the first time from the Misiones Province (NE Argentina). Complete description and illustration of the species are provided.

  Two New Zealand liverworts, Isotachis lyallii Mitt. and I. montana Col. have been chemically investigated. The former species produces a tetracyclic sesquiterpene hydrocarbon, anastreptene, two aromatic esters, benzyl benzoate and β-phenethyl trans-cinnamate as the major components. The latter species contains a newly recognized aromatic ester, β-phenethyl 4-hydroxy-3-methoxybenzoate, and two sesquiterpene hydrocarbons, bicyclogermacrene and anastreptene as the major components. Two unidentified Peruvian Isotachis species have been also analyzed by GC-MS. Both species produce not only benzoates and cinnamates, but also trans-β-methylthioacrylates which have been isolated from Japanese Isotachis japonica Mitt. The chemosystematics of Isotachis species is discussed.

  The bisbibenzyls marchantin C and riccardin A along with the previously known eudesmane (+)-ent-selin-1 1-en-4β-ol were isolated from the liverwort Riccardia nagasakiensis. Phytol and the sesquiterpenoids β-elemene, longifolene, γ-cadinene and spathulenol were detected by GC-MS. Chemosystematics of some Riccardia species will be discussed.

  This paper gives an account of all fully characterized flavonoids that have so far been isolated from arthrodontous mosses, and presents also the results of our extensive qualitative studies by 2 D-thin-layer chromatography on the occurrence of flavonoids in these mosses. Altogether nearly 300 species from 59 different families have been studied so far. It is shown that biflavonoids are by far the most common flavonoids in mosses and have been detected in more than two thirds of all species. Flavonoid glycosides, which are very common in hepatics, are, on the contrary, much rarer in mosses; they could be detected in only one fourth of all moss species tested.