North and South America share about 675 species that show two basic patterns, namely, those with a continuous range and those with a disjunct distribution. Both may have resulted from step-bystep migration, but the latter, including 118 species, may be due to break up of previous distributions by post-Tertiary tectonic and climatic changes or by long-distance dispersal.

Ten moss species - Garkea flexuosa (Griffith) Marg. & Nork., Campylopus laxitextus Lac., Fissidens dubius P. Beauv., Fissidens ceylonensis Dozy & Molk, Fissidens maceratus Mitt., Philonotis thwaitesii Mitt., Isopterygium minutirameum (C. Muell.)Jaeg., Homalia trichomanoides (Hedw.) B.S.G., Pogonatum neesii (C. Muell.) Dozy and Polytrichum formosum Hedw. are reported new to Hong Kong. Among them, five are new to Guangdong Province of China.

Ten moss species - Thamnobryum plicatulum (Lac.) Iwats., Ditrichum pallidum (Hedw.) Hampe, Brachythecium moriense Besch., Eurhynchium hians (Hedw.) Lac., Atrichum undulatum (Hedw.) P. Beauv., Bryum coronatum Schwaegr., Pseudoleskeopsis zippelii (Dozy & Molk.) Broth., Weissia controversa Hedw., Trichosteleum mammosum (C. Muell.) Jaeg. and Vesicularia reticulata (Dozy & Molk.) Broth. are reported new to Hong Kong. Among them, seven are new to Guangdong Province of China.

Ten moss species - Philonotis turneriana (Schwaegr.) Mitt., Fissidens javanicus Dozy & Molk., Lopidium nazeense (Ther.) Broth., Himatocladium cyclophyllum (C. Muell.) Fleisch., Homaliodendron exigiuum (Bosch & Lac.) Fleisch., Homaliodendron microdendron (Mont.) Fleisch., Homaliodendron scapellifolium (Mitt.) Fleisch., Pinnatella anacamptolepis (C.Muell.) Broth., Calyptothecium wrightii (Mitt.) Fleisch. and Haplocladium angustifolium (Hampe & C. Muell.) Broth. are reported new to Hong Kong. Among them, four are new to Guangdong Province of China. An updated checklist of Hong Kong mosses is provided.

The species of Drepanolejeunea (D. mosenii (Steph.) Bischl.) and Leptolejeunea (L. exocellata (Spruce) Evans) found in the province of Misiones, Argentina, are described and illustrated. The two genera, members of the subfam. Lejeuneoideae, are new records of Misiones. Drepanolejeunea sabaliana Schust. is proposed as new synonym of D. mosenii.

The three species of Aphanolejeunea (Lejeuneaceae, subfam. Lejeuneoideae) found in Misiones, Argentina: Aphanolejeunea missionensis Reiner sp. nov., A. paucifolia (Spruce) Reiner comb. nov. and A. clavatopapillata (Steph.) Reiner comb. nov., are described and illustrated. A. tuberculata (Evans) Schust. and Cololejeunea cristallina Herz. are proposed as new synonyms of A. clavatopapillata

194 species of bryophytes, belonging to 61 families are reported from Mount Kenya, of which 38 species are new for Mount Kenya and 30 records are new for the whole country, marked by * and ** respectively. The montane forests between 1600 and 3300m. asl., contain the greatest diversity of life forms and species. This is due to the abundant rainfall providing adequate humidity at relatively low temperature and altitude, coupled with frequent cloud cover. All vegetation belts above the montane forests experience large diurnal fluctuations in temperatures, intense solar radiation, added by the fact that the rainfall is relatively low and erratic or at times fall in the form of hail or snow resulting in a low diversity of species and life forms except in very sheltered habitats such as rock crevices in rocky outcrops. Solifluctions soil conditions occuring between 3850 and 4450m. asl. exhibit moss balls growth forms. The summits of Batian (5199m.), Nelion (5188m.) and Lenana (4985m.) harbour small cushions of Grimmia affinis and Andreaea cucullata. The greatest number of species are found in the wetter southern, south-western and south-eastern slopes unlike the drier northern, north-western and north-eastern slopes of the mountain. Species commonly found in the wetter areas are Bryum preussii, Bryum keniae, Prionodon ciliatus, Hypopterygium viridissimum, Plagiochila barteri, Plagiochila squamulosa, Radula recurvifolia, Porella hoehnelii, Dumortiera hirsuta while Pterogonium gracile, Leptodon smithii and Hedwigia ciliata are characteristic of the drier areas.

Distichophyllum meizhii Tan & Lin and D. wanianum Tan & Lin (Hookeriaceae) collected from southwestern region of China are described as new to science. Also, Horikawaea redfearnii Tan & Lin is described as a new species based on collections from Hainan Island of China and Palawan Island of the Philippines. The sporophytic specimen of Horikawaea Nog. was collected for the first time and support a family placement in Pterobryaceae.

The following twenty three new combinations and new names are proposed for Chinese moss taxa: Barbula chenia, B. dixoniana, Barbula propaguliferum, Bryum ochianum, Chrysocladium retrorsum var. pinfaense, Dicladiella trichophora, Didymodon rigidulus var. perobustus, Entodon caliginosus var. subtilis, Microdus brotheri, Platydictya sinensis-subtilis, P. yuennanensis, Pohlia cavalieri, P. ciliifera, C. graciliformis, P. laticuspes, P. propagulifera, P. pygmaea, P. tapintzense, P. timmioides, Sinskea flammea ssp. ochracea, S. flammea ssp. rufifolioides, Trichostomum sinochenii and T. zanderi.

A total of 34 bryophyte species were identified (25 hepatics, 9 mosses) from restinga at Setiba State Park, Guarapari Municipality, Espírito Santo State, Brazil. Several species reported previously from restinga appear to be erroneous records, based on misidentification.

Diplasiolejeunea involuta Winkler, a species formerly known only from El Salvador, was collected from shrubs in a non pure Sphagnum - Blechnum bog in Costa Rica. The plant is easily recognized by its large leaves, very convex lobes and very large lobules with obviously involute apex; the species has 3-7 oil bodies of the Jungermannia type per cell. Most characteristics of D. involuta fit with those of the subgenus Austrolejeuneopsis, the size of the underleaves are like those of the subgenus Diplasiolejeunea and the stout lobule covers up to 85% of the lobe, as in the subgenus Physolejeunea.

Interesting records of bryophytes from Zaire are listed, of which 24 taxa are reported for the first time for this country. Pohlia proligera is recorded as new for tropical Africa.

2939 moss taxa are listed for sub-Saharan Africa and adjacent islands, with distribution by country. Each distribution record is supported by a literature reference. The following new combinations are made: Calyptrochaeta cristata (Hedw.) O’Shea, Groutiella elimbata (Thér) O’Shea, Meiothecium undulatum (Ren. & Card.) O’Shea, Orthodontium ruwenzorensis (Thér. & Nav.) O’Shea, Pohlia lacouturei (Thér.) O’Shea, Sematophyllum corticolum (Aongstr.) O’Shea, Sematophyllum dixonii (Thér.) O’Shea, Sematophyllum nanopyxis (Geh.) O’Shea, Sematophyllum rigescens (Card.) O’Shea, and Thamnobryum malgachum (Card.) O’Shea.

Secalonic acid A, a yellow pigment from fungal metabolism, was isolated from the lichens Pseudoparmelia sphaerospora and P. hypomilta. From P. sphaerospora was also isolated the depsidone hypostictic acid. The structure of these compounds was determined by spectroscopic methods and comparison with literature data.

Nomenclatural changes are presented for eleven species of the genus Arthothelium, resulting in four new combinations and five new synonyms. The new combinations are: Arthothelium subbessale (Nyl.) comb. nov., Cyclographina circumscissa (Vain.) comb. nov., Minksia angolensis (Nyl.) comb. nov. and Thelotrema puniceum (Müll. Arg.) comb. nov. In addition, a new species is described, Arthothelium endoaurantiacum.

Nine species of the genus Coccocarpia are reported from Venezuela, including two new species from the states Mérida and Amazonas. These species are: C. culatensis sp. nov. (Andes), C. domingensis Vain., C. duidensis sp. nov. (Amazonas), C. epiphylla (Fée) Krempelh., C. erythrocardia (Müll. Arg.) L. Arvidss., C. erythroxyli (Spreng.) Swinsc. & Krog, C. imbricascens Nyl., C. palmicola (Spreng.) L. Arvidss. & D. Gall. and C. pellita (Ach.) Müll. Arg. emend. R. Sant. Descriptions, a key and comments on distribution and ecology are presented.

Several new synonyms are recognized for Colombian taxa: Aongstroemia maculata = A. julacea, Callicostella acutifolia and C. plicatula = Thamniopsis diffusa, Dicranella mayorii and D. peruviana = D. hilariana, Glyphomitrium lobuliferum = Ptychomitrium lindigii, Trichostomum novo-granatense = T. brachydontium; and for Ecuadorean taxa: Grimmia cinerea = G. longirostris, Grimmia benoistii = G. trichophylla, Neckera benoistii = N. chilensis, Orthostichopsis incertus = Porotrichendron superbum, and Renauldia obovata = Neckera obtusifolius. Additional Colombian synonyms recognized by specialists are listed.

Eight species of Radula (R. macrostachya Lindenb. & Gott., R. episcia Spruce, R. kegelii Gott. ex Steph., R. ligula Steph., R. aurantii Spruce, R. montana Steph., R. quadrata Gott. and R. voluta Tayl.) are found in the province of Misiones, and two species (R. aurantii and R. kegelii) in Buenos Aires. These are described and illustrated, and habitat and geographic distribution of the species are indicated. Keys for the identification of these species and a synopsis with their systematic position are provided. R. ligula is transferred to the section Marginatae Castle ex Grolle. R. flaccida Lindenb. & Gott. is excluded from the study area.

Based on the gametophyte characters, Porothamnium ceylonense Fleisch. is transferred to Thamnobryum Nieuwl. and the combination T. ceylonense (Fleisch.) Enroth is made. The species is lectotypified and line drawings of it are provided.

The following new records are presented: Solomoon Islands: Plagiotheciopsis oblonga (Broth.) Broth.; Malaysia: Neckera warburgii Broth. (Himantocladium warburgii (Broth.) Fleisch.); Vietnam: Taiwanobryum speciosum Nog.; Laos: Himantocladium formosicum Broth. & Yas.; India: Thamnobryum alleghaniense (C. M?ll.) Nieuwl.; Nepal: Himantocladium cyclophyllum (C. M?ll.) Fleisch.and Homaliadelphus targionianus (Mitt.) Dix. & P. Varde; Bhutan: Neckera muraetae Nog., N. polyclada C. M?ll., Neckeropsis exserta (Hook.) Broth., Himantocladium cyclophyllum, Pinnatella alopecuroides (Hook.) Fleisch., P. calcutensis Fleisch., Porotrichum fruticosum (Brid.) Jaeg. And Handeliobryum sikkimense (Par.) Ochyra. Hypnum schmidii C. M?ll. (Thamnobryum schmidii (C. M?ll.) Chopra) is lectotypified and symnonymized with Thamnobryum alleghaniense. Discovery of the sporophyte of Himantocladium warburgii indicates that the species belongs to Neckera Hedw.

A Nowellia curvifolia community rich in boreal hepatics is reported fromrotten logs in a pine forest in the central highlands of Chiapas, Mexico. The community is probably limited in the tropics to conifer forests of northern Mesoamerica. Nowellia curvifolia is reported as a new to Brazil and the southern heimisphere, Cephalozia catenulate is new to Guatemala and Honduras and Cephalozia lunulifolia is new to Guatemala

Thirty-seven species of hepatics and 66 species of mosses are reported from Heishiding Nature Reserve, including eight taxa new to China and one species new to mainland China. The new taxa for China are Ectropothecium aneitense Broth., Gammiella tonkinensis (Broth. & Par.) Tan, G. touwii Tan, Hypnum fauriei Card., Papillidiopsis complanata (Dix.) Buck & Tan, Syrrhopodon prolifer Schwaegr. var. papillosum (C.M?ll.) Reese, Trichosteleum pseudo-mammosum Fleisch., and Trichostomum crispulum Bruch; and the species new to mainland China is Isocladiella surcularis (Dix.) Tan & Mohamed. The phytogeography of the area and the bryophytes are discussed.

The phytogeography of Western Melanesian (Papua New Guinea, West Irian and the Solomon Islands) Lejeuneaceae was studied on the basis of previous literature and the Huon Peninsula material from the Koponen-Norris expedition. The largest portion of the Lejeuneaceae belong to Western Melanesian and Malaysian endemics. The number of Western Melanesian endemic Lejeuneaceae (20.5 %) is, however, somewhat lower than generally in hepatics (38.2 %). This is apparently due to the large number of epiphyllous taxa in the Lejeuneaceae, a group especially widespread in lowland rainforests.

Bryophytes have been collected during a survey of the vegetation of Inselbergs in western Africa in Ivory Coast, Senegal and Guinea, which are rather undercollected areas. The identifications revealed 43 new records for these countries. Inselberg habitats are considered to provide constant ecological conditions over long periods and varying climatic conditions. They can be regarded as refugia for dry adapted species during humid periods which could expand to the surrounding savannahs in dry periods. A new combination (Archidium globiferum [Brid.] J.-P. Frahm) is introduced for Archidium ohioense Schimp. ex C. M?ll.

A survey of the bryophyte flora of Rio Branco Municipality, State of Acre, Brazil, has revealed a total of 76 species of bryophyte; 66 are new records for the State of Acre and two hepaticas, Cololejeunea dzumacensis P. Tix. and Lejeunea bermudiana (Evs.) Schust., are new records for Brazil. The Anthocerotae are represented only by Notothylas vitalii Udar & Singh.

New country records and range extensions for several pottiaceous mosses, mostly from S.E. Asia, are reported. Thirteen new synonyms are proposed.

The two species of Cololejeunea (Lejeuneaceae subfam. Cololejeuneoideae) found in Misiones, are described and illustrated. C. minutissima subsp. myriocarpa (Nees & Mont.) Schust. is registered for the first time for the provinces Misiones, Formosa and Corrientes in Argentina and for Paraguay; C. spegazzinii (C. Mass.) C. Mass., Lejeunea myriandroecia Spruce and C. myriantha (Herz.) S. Arnell are proposed as new synonyms of this subspecies. C. cardiocarpa (Mont.) Evans is registered for the first time for Argentina (provinces Misiones, Corrientes and Buenos Aires) and for Paraguay.

The Choco region in Colombia harbours one of the wettest rainforests in the world. Isolated for about 3 million years, is it known for its high rate of endemism in flowering plants, birds and butterflies, Bryologically it is, however, very unsufficiently know. For this reason, a transect was investigated from sea level to 1800 m elevation. Ten hectarplots were studied at different altitudes. 125 species of mosses were identified, of which 45 are new records for the departments of Choco or Risaralda and 17 species are new record for Columbia. Holomitrium aberrens J.-P. Frahm is described as new. The floristic result allow a first evaluation of the bryological role of this region. With 3 endemic species, endemics of mosses in Choco region is not as high as in other group of organisms. Bryologically, the special characteristic of the Choco mossflora seems to be a meso American floristic element, to which 15% of the species belong. Part of the endemic species of mosses occur also in Panama. It is therefore supposed that the Choco phytogeographical element is not confined to northern Ecuador and Colombia but continues into the isthmus of Panama

The vegetative and sporophytic features of Holomitriopsis that distinguish this genus from Schistomitrium and from Leucobryum are discussed and illustrated using scanning electron microscopy.

No bryophyte conservation programs are in place in Australia as the knowledge of bryophytes is poor, especially of their habitat preferences and distribution. The conservation of species against habitats is discussed and it is maintained on present evidence that areas conserved for vascular plants and/or animal habitats, as national parks and forest reserves, in most cases would adequately conserve bryophytes.

Along a transect from 900 m to 3300 m elevation, various ecological parameters concerning epiphytic bryophytes have been studied. The most characteristic life form between 900 and 2300 m elevation is the dendroid, which is interpreted as an adaptation to better gas exchange under the unfavourable conditions (low light, high air humidity) of the rain forest. Above 2500 m, cushions are the predominant life form. The cushion are 2-5 cm high but can reach 50 cm at the forest line. In spectacular cases, moss balls are formed up to 1 m in diameter. PH measurements of the bark of host trees revealed values between 4.1 and 6.2, which is in accordance with results from South America and SE-Asia. The bryophyte cover on soil is very low (<5%) below 2700 m but raises to 90% in the subalpine ericaceous belt, but not in the subalpine Senecio-belt. The percentage cover of bryophytes on bark increases from 5 to 80% in the transect with increasing elevation, and the light intensity increases from 4%to 50%. The mean annual temperature decreases continuously from 20.6?C at 900 m elevation to 2.5? at 4500 m elevation. This allows a comparison of the growth conditions of bryophyte species occurring disjunct in the oceanic parts of the temperate regions and the tropical mountains. The phytomass of epiphytic bryophyta per m2 and per ha increases synchronously in the transect. There is a sudden increase from 8 - 44 kg/ha in 900 - 1300 m to 100 - 600 kg/ha in elevations between 1900 and 2900 m. Maximum values of 6 tonnes/ha are found at the forest line, being 750 times higher than the lowest value in the lower part of the transect. The water storing capacity of epiphytic bryophytes is 20-60 l/ha at elevations between 900 and 1300 m, 130 - 2000 l/ha between 1900 and 2900 m and 18000 l/ha at the forest line. The latter is 18% of the estimated rainfall.

The altitudinal zonation of the tropical rain forest at Mt. Kahuzi has been studied using bryophytes. The study is based on floristic parameters such as the number of species per hectarplot in different altitudes and the calculation of floristic discontinuities extracted from an evaluation of altitudinal ranges. The results are compared and correlated to ecological parameters, especially data on the phytomass of epiphytic bryophytes per m2 and per hectare. Based on these data, the tropical rain forest is classified as submontane forest (- 1500 m), lower tropical montane forest (1500-2000 m), upper tropical montane forest (2100 - 2800 m), and subalpine forest (2900 - 3200 m). Except for the terminology, the vegetation belts derived from bryophytes can be correlated with those presented in general vegetational schemes for tropical Africa.

During the BRYOTROP-Expedition to Zaire and Rwanda bryophytes were collected from a rainforest habitat at 800 m a.s.l. and from bamboo forest and tree-heath environments between 2200 and 3200 m. The microclimates influencing the mosses are different at the altitudinally separated locations. Conditions are rather constant with 24 ?C, 100 % rel. hum. and PAR below 100 ?mol photons m-2 sec-1 at the lowland station, rather versatile in the mountains with six times higher daily sums of PAR, temperatures between 10 and 25 ?C and relative humidities between 60 and 1oo %. In the bamboo forest epiphytic mosses dry out during the day to less than 70 % of their water content, but regain saturation from the vapor-saturated air during night. Bryophyte photosynthesis and respiration were studied by Warburg manometry with moisture saturated samples. Temperature curves of gas exchange peaked between 22 and 30 ?C. Optima of the lowland species were somewhat higher than those from samples collected at the mountain sites. Habitat separation of characteristics of photosynthesis was more pronounced with respect to light responses. Saturation gas exchange rates were reached by all species still below 400 ?mol photons m-2 sec-1. But the slopes of the curves in the low-light range were distinctly steeper, and the light compensation points smaller in the lowland than in the highland species (compensation points of the former: 3 - 12 ?mol photons m-2 sec-1, of the latter: 8 - 20 ?mol photons m-2 sec-1). It is emphasized that bryophytes in the rainforest understory experience extremely high ambient C02 concentrations near the floor. This, their low light requirements for photosynthesis, and the permanently optimal temperature and humidity conditions for maximal carbon gain enable them to live successfully, but with less biomass development in this dark and damp environment. By contrast, bryophytes from the bamboo forest and tree-heath environments can utilize light conditions combined with variable temperatures and humidities similarly as species from extratropical vegetation types.

The group of Ramalina cochlearis Zahlbr. and its allies in tropical America have been Revised. Ramalina cochlearis is reported from four countries: Mexico, Honduras, Columbia and Venezuela. Ramalina ecorialensis and R. vareschii, both from the Venezuelan Andes, and R. xalapensis from Mexico are described as new. A key and descriptions are provided.

Ramalina subfraxinea Nyl. var. confirmata (Nyl.) N. Stevens is reported as a new to the New World from the Venezuelan Andes. Thus far this variety was know only from Australia, New Caledonia and the Indian Ocean. It has cryptochlorophaeic acid as chemical compound. Comments about ecology and morphology are given.

A short survey of the bryological exploration of Rwanda and Zaire is provided. The first to collect bryophytes in the area was Stuhlmann in 1891 on Ruwenzori. The first bryological collections from Rwanda were made by Mildbraed in 1907. In 1929 Humbert made the first gatherings on Mt. Kahuzi and Mt. Biega. Since then a lot of botanist have collected mosses and liverworts so that Rwanda and eastern Zaire can be regarded as well known. From most parts of Zaire and from Burundi however only few data are hitherto available.

During the BRYOTROP-Expedition in 1991, 71 collecting sites could be visited. These are situated in the Kahuzi-Biega-National Park/Zaire, the Nyungwe Forest and the Virunga volcanoes/Rwanda. This paper provides a short description of the vegetation in these three areas and a detailed list of all collecting sites.

Four Riccia species, namely R. lanceolata, R. okahandjana, R. stricta and R. vulcanicola of the hepatic family Ricciaceae (order Marchantiales) from Rwanda and Zaire are described and illustrated in this report. Riccia lanceolata and R. stricta are new records for Rwanda

A new Riccia species, R. vulcanicola is described and illustrated. It is closely related to R. crystallina, differing by the incomplete rosettes of the thallus and the larger and fewer areolae of the spores.

A survey of the families Trichocoleaceae, Geocalycaceae, Acrobolbaceae, Balantiopsidaceae, Lepidoziaceae (Telaranea, Arachniopsis), Calypogeiaceae, Adelanthaceae, Porellaceae, Jubulaceae, Marchantiaceae (Dumortiera) (Hepaticae) and Polytrichaceae (Musci) for Central Africa (Zaire and Rwanda) is presented. Leptoscyphus infuscatus, Tylimanthus ruwenzoriensis, Calypogeia fissa, Adelanthus lindenbergianus and Porella subdentata are recorded as new to Rwanda. Telaranea trifida and Calypogeia fusca are new to Zaire. Leptoscyphus hedbergii and Calypogeia afrocaerulea are new records for Zaire and Rwanda.

Thirteen new records of species of Andreaea, Trematodon, Campylopus and Rhabdoweisia for Rwanda viz. Zaire are published. Campylopus cerradensis Vital and Paraleucobryum longifolium (Hedw.) Loeske ssp. brasiliense (Broth.) P. Müller & J.-P. Frahm, previously only known from Brazil, are reported for Africa for the first time. Campylopus schmidii C. Müll. is reported for the first time for the African continent. Campylopus leucochlorus is regarded as synonymous with C. hildebrandtii (C. Müll.) Jaeg. Atractylocarpus capillifolius Dix. is regarded as synonymous with A. alticaulis (Broth.) Williams. Based on a different spore size, spore ornamentation and growth form as well as cultivation experiments, Antitrichia kilimandscharica Broth. is regarded as separate species and not as synonymous with A. curtipendula (Hedw.) Brid. Acrocryphaea robusta Broth. in Mildbr. is combined new to the genus Schoenobryum.

The total number of currently accepted species of Cladoniaceae in the Hawaiian Islands is 22. Several taxonomic problems still exist, however. The effects of isolation are clear among Cladoniaceae. Endemism is high (c. 40%); and, the number of species low. The species must have reached the archipelago via long-distance trans-oceanic dispersal, probably aided by the abundant production of lichen propagules, such as soredia and microsquamules. Although most of the species found in Hawaii are widely distributed, the Hawaiian Cladoniaceae show slight affinities to those of E and SE Asia. Cladonia polyphylla Mont. & v.d. Bosch is an older name for C. fruticulosa Krempelh., and is lectotypified from authentic material. C. leprosula H. Magn. is included in C. ochrochlora Flörke.

286 species of lichenized fungi on Mount Kinabalu are recorded by field survey and investigation of literature records and herbarium material. An annotated catalogue is presented, together with habitat notes, and a list of collectors. The summit area has a saxicolous lichen flora of boreal affinities, while the lower zones are more closely related to other SE Asian mountains. Eleven species appear to be restricted to the mountain, and four new species are described: Phaeographis kinabalensis, Stereocaulon granulans, Pertusaria epitheciifera and Thelotrema subweberi.

A new species of Cronisia with sessile dorsal female involucres is described from Mexico. This plant, C. mexicana, is compared to C. paradoxa and to other species with similarly placed female involucres.

The West Indies have strong continental affinities, but the strongest are with South America, not Central America as was once thought. Moss diversity is the result of migration after the Miocene; the patterns of distribution involving the West Indies and South or North America indicate both migration as well as floristic flows through the Antillean Arc. Speciation due to selective pressures in the changing climate of the Pleistocene gave rise to endemic taxa, but paleoendemics may have resulted in a previous archipelago condition.

Seventeen species of holostipous (underleaves undivided) Lejeuneaceae (Jungermanniales) found in the province of Misiones, Argentina, are described and illustrated. The species are members of the subfamilies Lejeuneoideae and Ptychanthoideae and belong to the genera Anoplolejeunea, Lejeunea, Leucolejeunea, Omphalanthus, Acanthocoleus, Archilejeunea, Brachiolejeunea, Bryopteris, Caudalejeunea, Frullanoides, Lopholejeunea, Marchesinia, Mastigolejeuena, Odontolejeunea and Schiffneriolejeunea. All of the species are new records for Misiones and, with exception of Omphalanthus filiformis and Frullanoides densifolia (known for the province of Salta), all of them are new records for Argentina. For each taxon the habitat and the geographical distribution are indicated. A key to the species and synopsis of their systematic position are also provided.

Thirty-seven species of mosses are reported from the Mascarenes and three are republished under new names. Didymodon michiganensis (Steere) K. Saito is new to Africa. Campylopus bartramiaceus (C. Muell.) Th?r., Pogonatum proliferum (Griff.) Mitt. and Zygodon intermedius B.S.G. are new to the Mascarenes. Calymperes palisotii ssp. palisotii Schwaegr. is new to Mauritius.

Field and herbarium studies of the lichen family Cladoniaceae in the states of Para?ba, Pernambuco and Sergipe, Northeast Brazil, yielded 22 species, many of them being new reports for the region. The phenolic compounds identified in each species are reported. Cladonia clathrata Ahti & Xavier Filho, Cladonia polita Ahti, Cladonia polyscypha Ahti & Xavier Filho, and Cladonia rugicaulis Ahti are described as new. C. clathrata, C. rhodoleuca Vainio, C. rugicaulis, C. salzmannii Nyl., and C. subminiata Stenroos appear to represent an element confined to northeastern Brazil.

Lecanora leprosa and L. sulphurescens are two commonly misidentified pantropical lichens. A detailed circumscription is presented to help overcome such difficulties. Both species contain a chemosyndrome of chlorodepsidones based on gangaleoidin. The new depsidone chlorolecideoidin (methyl 2,4,9-trichloro-3,8-dihydroxy-1,6-dimethyl-11-oxo-11H-dibenzo[b,e][1,4]-dioxepin- 7-carboxylate) has been shown to be a minor component of both species.

A list is provided of 263 neotropical species of bryophytes (141 mosses, 122 hepatics) distributed in Bryophyta Neotropica Exsiccata, Fascicles I-VI (1984-1992).

A new, phyllidiate, white-medulla species with yellow pseudocyphellae and a green photobiont, Pseudocyphellaria kalbii D.J.Galloway, is described from Brazilian collections, and typification and notes on P. aurora (De Not.) Vainio are presented.

Bibliographic records are presented of 324 scientific papers on foliicolous lichenized fungi published subsequent to Santesson’s survey of 1952. The 482 species presently known are listed in an alphabetical checklist, with references to important descriptions, keys and illustrations published by or after Santesson (1952), and an indication of the distribution. Also added are all synonyms used after 1952. Introductory chapters deal with the present state of research on foliicolous lichens and its history. The following new combination is proposed: Strigula smaragdula Fr. var. stellata (Nyl. & Cromb.)Farkas.

Upon examination of type material, the following new synonymies are proposed: Macromitrium altituberculosum Bartr. with M. carionis C. Muell.; M. aureum C. Muell. with M. longifolium (Hook.) Brid.; M. crumianum Steere & Buck with M. leprieurii Mont.; M. semimarginatum C. Muell. with Groutiella chimborazense (Spruce ex Mitten) Florsch.; M. standleyi Bartr. var. subundulatum Bartr. with M. fulgescens Bartr. In addition, the following synonymies were confirmed: M. brevipes C. Muell. with Groutiella apiculata (Hook. & Grev.) Crum & Steere; M. sartorii C. Muell. with M. punctatum (Hook. & Grev.) Brid. Floristic reports include M. leprieurii new to Dominica, Guadeloupe, and Panama, and M. ulophyllum Mitten is reported for the first time from Central America (Panama) and Venezuela. A complete description including illustration is provided for the first time for the latter species. Lectotypes are chosen for all types examined.

214 Lichens and 38 bryophyte species are reported from Cerro Guaiquinima, a sandstone table mountain in southeastern Venezuela, thus far almost unexplored for these groups and apparently undisturbed by man. Slightly over half of these species have also been reported from the noth slope of Mount Roraima and surroundings, a nearby area with similar edaphic and climatological conditions. Altitudinaldifferences in the flora are probably largely dependent on differences in vegetation structure: the closed forests at the foot harbour more Thelotremataceae, whereas in the open vegetation of the rocky plains on the summit more Cladoniaceae and Trypetheliaceae are found. On the highest site bryophytes are more frequent. First descriptions are given for nine lichens and one moss: Buellia bellardii Sipman, Hypotrachyna adaffinis Sipman, Myriotrema flavolucens Sipman, Myriotrema squamuloides Sipman, Ocellularia croceoisidiata Sipman, Ocellularia glaucoglyphica Sipman, Thelotrema carneoradians Sipman, Thelotrema guaiquinimae Sipman, Sphagnum sipmannii Crum and Ocellularia sinuosa Sipman (in appendix, from Colombia). Myriotrema guianense is reduced to synonymy of Myriotrema columellatum (A. Zahlbr.) Sipman, comb. nov.

The bryophyte collection at MEXU was formally established in 1973 with about 3000 Specimens; at present, it contains nearly 35,000. Emphasis has been made on Mexican and tropical American localities, but herbarium holdings also include temperate areas. Herbarium information is now being stored in a database to assist floristic and taxonomic research in progress and for further reference.

The vascular flora of Chiapas, Mexico, has been the subject of a long term study by Dennis Breedlove of the California Academy of Sciences. This has stimulated a related project dealing with the bryophyte flora of the region. A collecting expedition in 1988 generated 1420 collections of bryophytes. Specialists from 13 institutions assisted with identifications. Approximately 70% of the collections have been determined. Checklists of species of bryophytes of Chiapas are presented. These lists are based on collections at CAS and literature citations. A total of 364 species of mosses and 310 species of hepatics and hornworts are reported from Chiapas.

The teaching of bryology in Mexico confronts various difficulties that prevent students from having at least a broad overview of what bryophytes are. There are three main problems: lack of institutional facilities, lack of specialized literature and ignorance of the structure, biology and significance of these plants on the part of teachers. To resolve these difficulties, schools must obtain the minimum necessary facilities (Microscopes, laboratory materials ans specialized literature) and request specialists to teach courses and colaborate in workshops and fieldtrips to give teachers a better understanding of bryophytes.

LATMOSS is a data bank for mosses known from the neotropical area. The geographical data contained therein are being used to study phytogeographical patterns and propose explanations to the distribution of neotropical mosses. It currently contains 4129 entries.

Scanning electron microscopy and light microscopy were used to elucidate the morphology of Metzgeria conjutata Lindb. and confirm the presence of 2 rows of epidermal cells on the dorsal surface, (21-3) rows on the ventral surface, midrib with cells in (3-51-6) tiers; hirsute, short hairs, straight on the thallus-margin and on the ventral surface of midrib; marginal hairs paired, single or in groups of three; male branches globose or subglobose; female involucres obovate and hirsute at the margin, calyptra fleshy, pyriform to club-shaped, hirsute on the outer surface, hairs long and straight.

The Index of Atmospheric Purity (IAP) was used to make a preliminary evaluation of epiphytic moss response to atmospheric pollution in the urban area of Mexico City. Areal analysis indicates that there is a significant negative correlation (p < 0.5) between IAP values and SO2, NO2, NOx, Pb and temperature values of -0.45, -0.90, -0.80, -0.80, -0.90. Significant positive correlation (p < 0.05) between IAP values and O3, rainfall and relative atmospheric humidity with values of 0.70, 0.80, 0.90. Increase in atmospheric pollutants in Mexico City have promoted a gradual decrease in frequency and cover of epiphytic mosses even though some ecological factors may show the oposite effect.

Tropical deforestation, inevitably, leads to the local loss of bryophyte species. Recent studies show that the degree of species loss may vary considerably and depends on the scale or amount of habitat change that has occurred. Predictably, the shade epiphytes are most seriously affected by disturbance. An estimated 10% of the bryophyte species of neotropical rain forests are under threat. Based on data from recent monographs, a first list of 19 endangered and 27 rare species of these forests is presented. Critical areas for threatened species include Costa Rica and Panama, the Greater Antilles, the Chocó, southeastern Brazil, and parts of Amazonia. Protection of as much as possible of the remaining natural rain forest area seems the best approach to the conservation of the tropical bryophyte flora.

The phylogenetic relationships of the species of Anomodon are analyzed along with those of Haplohymenium and Herpetineuron. Anomodon is known only from the northern hemisphere: there are four species in Mexico (several of which extend to Guatemala and/or the Caribbean islands), two in the United States and Canada, on in Europe, and the remaining in south and east Asia. Three species of Haplohymenium, Herpetineuron toccoae, H. acutifolium (Anomodon acutifolius, Granzow- de la Cerda 1989) and Pterogonium gracile are also included. Thirty-one characters for the 17 taxa were analyzed by using the PAUP program, version 3.0, for Macintosh (Swofford 1991). According to the resulting trees, the 11 species of Anomodon are monophyletic as long as it includes the species of Haplohymenium. Anomodon comprises two clads, one equivalent to the subgenus Pseudoanomodon Limpr., including A. longifolius, A. attenuatus, A. giraldii and A. rostratus; the other is equivalent to subgenus Anomodon and includes the species of Haplohymenium. Section Haplohymenium is proposed for the latter genus.

Comments are given regarding a preliminary list of 48 families of mites collected on mosses in Mexico: 11 Mesostigmata, 17 Prostigmata (=Actinedida), 1 Astigmata and 19 Cryptostigmata (=Oribatei); a general analysis is made of the relationship between the bryophytes and their associated fauna. An in-depth study of this faunal group must reveal a much greater number of associated species.

The pleurocarpous moss genus Isopterygium (Hypnaceae) is revised for Latin America. Although as many as 92 species and varieties have been reported for the region over past years, these are currently accommodated by the present revision into only eight species. The most common taxon throughout most of Latin America, Isopterygium tenerum (Sw.) Mitt., is also the most polymorphic and presently 45 taxa are recognized as synonyms. The other seven species are I. affusum Mitt. (Guadeloupe, Honduras, Venezuela, Brazil), I. acutifolium Irel. (Venezuela, Guyana), I. byssobolax (C. Müll.) Par. (Brazil, Bolivia, Argentina), I. jamaicense (Bartr.) Buck (Mexico, Guatemala, Jamaica), I. subbrevisetum (Hampe) Broth. (West Indies, Costa Rica to Southern Brazil), I. subglosum Herz. (Bolivia), and I. tenerifolium Mitt. (West Indies, southern Mexico to northern Argentina).

The characteristics of a species of Aphanolejeunea collected at the San Ramón Biological Reserve, Alajuela, Costa Rica, are compared to those given in the description of Lejeunea heterophylla from Puerto Rico; they are conspecific. A. heterophylla is essentially different from A. exigua Evans.

This is an overview of the bryological studies for Venezuela comprising the period from the early XIX century to date. The main contributors to this field have been foreign bryologists whose work, unfortunately, has not been of interest to the Venezuelan botanists.

This paper introduces the up-dated taxonomic placement of 106 genera of Hepaticae and 233 genera of Musci known from Venezuela. Besides, a summarized version from the geographical distribution in Venezuela of 383 species of Hepaticae and 1009 species of mosses is presented. Information was derived from an exhaustive revision of bryophyte collections in the Venezuelan herbaria, and from publications about bryophytes collected in Venezuela. It is concluded that Venezuela, despite having been little explored, has a great bryophyte diversity. Many species are unknown and could disappear before collection and scientific analysis.

Cuba is one of the Greater Antilles islands with a diverse moss flora (383 infrageneric taxa) that is mainly distributed toward the mountain areas. Although studies on phytochemistry and antibiosis have been initiated, those in taxonomy must be continued at the same time.

Sex ratios were determined for 15 populations of Marchantia chenopoda L. along Puerto Rico. Sex was determined for twenty randomly selected individuals from each population. A female bias was observed in most populations. A census of reproductive structures of M. chenopoda was performed every two weeks in order to determine phenology. The highest archegoniophore count was observed to occur in January and February; minimum and maximum fertilization distances were 0.7 cm and 65 cm, respectively. Young sporophytes were most frequently observed at the beginning of the rainy season, in April and May. The highest frequency of mature sporophytes occurred during the dry season, in January and February. Capsules opened mostly during the heavy rainy season, from August to November. Protonemata were observed in the periphery of the population. Most young sporophytes aborted at the end of the moderate to heavy rainy season, from June to August. Immature gemmae cups were most frequent at the beginning of the rainy season, in April and May. Mature gemmae cups were observed throughout the rainy season, but were most frequent in September.

The family Lejeuneaceae is one of the main taxa in the Cuban liverwort flora. It is now being revised for the Flora of Cuba project, along with problems of study and geographical distribution. Specimens at HAC represent 39 genera and 152 species of Cuban Lejeuneaceae.

Out of 21 species of Octoblepharum validly published for the Neotropics only 9 are recognized at the present time. These are: O. albidum Hedw., O. ampullaceum Mitt., O. cocuiense Mitt., O. cylindricum Schimp. ex Mont., O. erectifolium Mitt., O. pulvinatum (Doz. & Molk.) Mitt., O. rhaphidostegium C. Müll., O. stramineum Mitt. y O. tatei (Williams) Bartr. According to the number of peristome teeth, there are two evolutionary lines: one with 16 and the other with 8. Members of the first line are all dioicous whereas those in the latter are either autoicous or dioicous. Phenological studies in three species of Octoblepharum in Panamá suggest the occurrence of pseudodioecism in autoicous species and the development of a greater number of male gametoecia and antheridia than female ones. Two peristome types are found in populations of O. albidum; one is vertically striated while the other is smooth. All species occur in South America and this is considered the center of origin and speciation for the genus.

The bryophyte communities growing on decaying logs in the subtropical wet forests of Puerto Rico are described. Logs were classified according to presence or absence of bark and wood texture. Logs with bark are dominated by members of the Lejeuneaceae and Calymperaceae. In softwood logs, Taxithelium planum and Isopterygium tenerum were abundant. It is suggested in a preliminary manner that due to low fluctuation of water content in heavily decayed logs, hygromorphic bryophytes are favored.

References are made to cytotoxic and/or antitumor compounds that have been isolated - ansamitocin P-3 from Claopodium crispifolium (Hook.) Ren. & Card. and Anomodon attenuatus Hueb., or an associated actinomycete, and ohioensins and pallidisetums from Polytrichum spp. Several hundred collections, which have been obtained from temperate regions of North America during 1990 and 1991, are currently being screened in new bioassays; active sesquiterpene lactones have been recently isolated from species of Porella. The methodologies of collecting and screening bryophyte samples are discussed with consideration to costs based on expected number of samples that might be collected in a day, the diversity in the collections as related to phytogeography and vegetation types, and the bryophyte cover that is vanishing in many forest regions of the United States. The difficulties in obtaining large collections for isolation of active agents are also discussed by example recollection of Claopodium crispifolium.

Floristic work in progress indicates that the bryophyte flora of Cuba comprises ca. 1,017 infrageneric taxa. This diversity is probably due to the geographical position of the island and its climatic peculiarities.