Meeting report
Bryological symposium
The rural setting of the Field Studies Council’s headquarters at Preston Montford, near Shrewsbury, provided very pleasant surroundings for the AGM and paper-reading meeting. Members were particularly impressed by the gargantuan carp in the pond. The meeting this year was a special occasion, because it was partly a celebration of the 80th birthday of one of the Society’s most senior members, Dr Eric Watson. The central event of the weekend was a dinner in Eric’s honour on Saturday night, complete with birthday cake. As well as giving a superb talk earlier in the day, Eric entertained the assembled bryological throng with an after-dinner speech that brought tears of appreciative laughter to the eyes. The characteristic efficiency with which Dr. Martha Newton organised the meeting, made it a great success. My thanks to all the speakers at the meeting for an excellent collection of talks. The following summaries have been provided by the authors.
Nick Hodgetts
Prof. F. Sack (Ohio State University): The bigger they are, the harder they fall: gravity and mosses.
Gravity affects mosses in many ways:
Evolution and Plant Mass: Mosses lack the evolutionary specialisations that enable larger land plants to withstand the significant compaction produced by their mass.
Development: There are some reports of gravity influencing development such as where side branches emerge in protonemata. More examples would undoubtedly be found if they were sought out.
Gravitropism: Gametophores and sporophytes are usually gravitropic and this is probably adaptive e.g. for spore dispersal. Protonemata, which germinate from the spore, are gravitropic as well, but not well studied. We studied gravitropism in protonemata of Ceratodon which grow up in the dark. Both gravitropic sensing and differential growth (curvature) occur in or close to the tip of the apical cell, and tip growth is tightly coupled to tip orientation. In horizontal protonemata, there is extensive sedimentation of amyloplasts in a specific zone located behind the apical dome. This sedimentation could function in gravitropic sensing since it precedes upward curvature. This hypothesis is also supported by data from centrifugation experiments.
In upward curving cells, microtubules become enriched in the lower flank of the Golgi zone behind the apical dome. We hypothesise that amyloplast sedimentation induces an enrichment in microtubules that results in upward growth. The ultrastructure of horizontal and vertical cells was compared quantitatively. It was found that each organelle is located in its characteristic distribution and that Golgi stacks are abundant where microtubules become enriched. But no effect of horizontal placement on organelle distribution could be detected. Also, unlike microtubules, microfilaments did not appear to change distribution. Thus, the mechanisms of sensing and differential growth are still uncertain.
Evolution and cytoskeleton: Some amyloplast sedimentation also occurs in vertical cells, but sedimentation is not complete except when protonemata are treated with microtubule inhibitors. This suggests that the cytoskeleton evolved, in part to prevent the stratification of organelles with respect to their densities.
Dr A.J.E. Smith (University of Wales, Bangor): The Hypnum cupressiforme aggregate in the British Isles.
The members of the Hypnum cupressiforme aggregate have been variously treated by different authors, from those who regard them as only forms or varieties of H. cupressiforme to others regarding them as distinct species. This variable treatment is due in part at least to lack of familiarity or misunderstanding brought about by inadequate or misleading descriptions and illustrations.
Examination of more than 500 mainly British and Irish specimens and analysis of seven characters revealed clearly that there are eight to a greater or lesser extent well-defined taxa. There is no one character that can be used to separate all the taxa, indeed what are good characters for determining one taxon may be of little or no use for determining others.
On the basis of a combination of gametophyte and sporophyte characters seven of the taxa are sufficiently distinct to be treated as species and one, less clear cut, as a variety. These are H. andoi A.J.E. Smith (H. mammillatum (Brid.) Loeske, nom. inval.), H. cupressiforme Hedw. s.s., H. jutlandicum Holmen & Warncke, H. imponens Hedw., H. lacunosum (Brid.) Hoffm. var. lacunosum, H. lacunosum var. tectorum (Brid.) Frahm, H. resupinatum Wils. and H. uncinulatum Jur.
From about 1850 onwards in the British Isles and elsewhere, H. lacunosum var. lacunosum and var. tectorum have been confused to such an extent that recent authors (e.g. Smith, 1978; Düll, 1985) have treated them as synonymous; only Watson (1981) has recognised them as distinct.
Ando (1992) recognises H. cupressiforme var. filiforme Brid. but says it does not occur in the British Isles, which is curious since Warburg (1963) records it from 105 British and Irish vice-counties. The variety is very slender with parallel branches and straight leaves, at variance with the descriptions in Dixon & Jameson (1924) and Nyholm (1954-1969), which after examination of material led me (Smith, 1978) to reduce var. filiforme to synonymy with the plant then known as H. mammillatum Brid. Examination of some 110 specimens labelled var. filiforme revealed that they were a random assortment of slender forms of H. andoi, H. cupressiforme s.s. and H. resupinatum. Like Ando (1992), I have seen no British material of var. filiforme.
Following the examination of further characters it is intended in due course to publish a liberally illustrated paper on the H. cupressiforme aggregate in the British Isles. In the meantime, a provisional key to the taxa is given below.
Provisional key to the taxa of the Hypnum cupressiforme aggregate
| 1 | Capsule ± erect and straight | H. resupinatum |
| Capsule inclined and curved or lacking | 2 | |
| 2 | Capsule with a mamillate lid | H. andoi |
| Lid rostellate or lacking | 3 | |
| 3 | Stems pinnately branched, alar cells usually enlarged or inflated | 4 |
| Branching irregular, alar cells ± uniform in size or enlarged only towards basal angles | 5 | |
| 4 | Plants pale green when fresh, stems green, common plant of heath, peaty soils, bogs | H. jutlandicum |
| Plants golden to brownish, stems reddish-brown, rare plant of wet heaths and bogs | H. imponens | |
| 5 | Plants very slender, leaves straight, not recorded from British Isles | H. cupressiforme var. filiforme |
| Plant size various, if slender then leaves homomallous or weakly to strongly falcate | 6 | |
| 6 | Plants robust, stems ± julaceous when moist with strongly concave imbricate leaves | 7 |
| Plants very slender to medium-sized, leaves weakly concave, not imbricate | 8 | |
| 7 | Plants golden-green to bronze, leaves falcate, sometimes strongly so, mostly 2-3 mm long | H. lacunosum var. lacunosum |
| Plants dull olive to brownish-green, leaves straight to weakly falcate, usually less than 2 mm long | H. lacunosum var. tectorum | |
| 8 | Leaves homomallous, ± straight, margin usually entire | H. resupinatum |
| Leaves weakly to strongly falcato-secund, margin entire or denticulate | 9 | |
| 9 | Alar cells usually excavate, often brownish, 5-8 at margin, increasing in size towards basal angle, N. Kerry | H. uncinulatum |
| Alar cells not or weakly excavate, not brownish, 7-15 at margin except in very slender plants, common | 10 | |
| 10 | Leaves weakly falcato-secund, hardly or not complanate, alar cells usually ± similar in size, mid-leaf cells mostly 52-88 µm long | H. cupressiforme var. cupressiforme |
| Leaves falcato-secund, strongly so and complanate at least in small forms, alar cells often increasing in size and sometimes inflated towards basal angle, mid-leaf cells mostly 24-60 µm long | H. andoi |
References
Ando H. 1992. Studies on the genus Hypnum Hedw. (VIII). Hikobia 11: 111-123.
Dixon HN, Jameson HG. 1924. The student’s handbook of British mosses. 3rd ed. Eastbourne: V.V. Sumfield.
Düll R. 1985. Distribution of the European and Macaronesian mosses (Bryophytina). Bryologische beitraege 5: 1-232.
Nyholm E. 1954-1969. Illustrated moss flora of Fennoscandia. Lund: Gleerup.
Smith AJE. 1978. The moss flora of Britain and Ireland. Cambridge: Cambridge University Press.
Warburg EF. 1963. Census catalogue of British mosses. 3rd ed. British Bryological Society.
Watson EV. 1981. British mosses and liverworts. 3rd ed. Cambridge: Cambridge University Press.
Prof. J.G. Duckett (Queen Mary & Westfield College, London) and Mr H.W. Matcham (Chichester): Gemmiferous protonemata; an overlooked dimension in the reproductive biology of mosses.
Whereas descriptions of diaspores, produced by leafy gametophores and underground rhizoids, are based largely on wild materials and are a standard feature in moss floras, those of protonemal gemmae (defined as propagules produced on above ground chloronemal filaments and possessing specific liberation mechanisms (Duckett & Ligrone, 1992) derive almost exclusively from cultured specimens and are rarely mentioned in these texts. Detailed scrutiny of the literature indicates that in only twenty species, from the 119 recorded as producing gemmiferous protonemata (the latter figure almost certainly inflated due to confusion with protonemal brood cells produced by redifferentiation of chloronemal cells in ageing cultures (Goode et al., 1993b)), have produced gemmiferous protonemata in culture and from these 44 have been discovered to be gemmiferous in nature. We estimate that 20-30% of all mosses probably possess gemmiferous protonemata.
In a minority of species (e.g. Diphyscium foliosum, Dicranella heteromalla, Dicranoweisia cirrata, Dicranum montanum, D. tauricum, Tortula muralis, Orthodontium lineare, Schistostega pennata, Rhizomnium punctatum, Zygodon spp., Orthotrichum spp., Isopterygium elegans) gemmiferous protonemata may be found at all times of the year, often forming extensive patches in niches where gametophores are depauperate (Duckett & Ligrone, 1994; Duckett & Matcham, in press). However, in the majority (e.g. Ceratodon purpureus, Dicranella staphylina, Encalypta streptocarpa, Funaria hygrometrica, Bryum spp., Mnium hornum) they appear to be highly transient and associated only with initial stages in colonisation, often preceding the full development of gametophores. Gemmiferous protonemata may be found in a variety of habitats from trees and rotten logs to bare soils and rock surfaces. Taxonomically they are widely distributed in the different orders of mosses but are notably rare in the Hypnobryales and have yet to be seen in the Fissidentales, Grimmiales and Polytrichales. Liberation mechanisms involve either severance along the middle lamella of the basal cell (Dicranum montanum, D. tauricum, Saelania glaucescens, Mnium hornum, Rhizomnium punctatum, Cryphaea, Leptodon, Homalia, Myrinia and all 18 members of the Pottiales studied to date) or the formation of specialised tmema (abscission) cells by an intercalary division associated with polarity reversal in the filament in question. The tmema cells themselves exhibit a range of severance mechanisms. In Bryum breakage occurs along an equatorial line of weakness in the original wall (Goode et al., 1993a), in Funaria, Ceratodon and Dicranella filament disruption is affected by the expansion of a new internal wall (Duckett & Matcham, in press) but in the Hookeriales swelling of the cell below the tmema cell leads to the rupture of the latter.
To date we have but scratched the surface of an area of bryology largely overlooked by taxonomists, ecologists and reproductive biologists alike. Some 25 years ago the late Eustace Jones remarked to one of us, when you start bryology you collect common species, then you stop but eventually you start again. Gemmiferous protonemata are a compelling reason for all of us to begin again.
References
Duckett JG, Ligrone R. 1992. A survey of diaspore liberation mechanisms and germination patterns in mosses. Journal of Bryology 17: 335-354.
Duckett JG, Ligrone R. 1994. Studies of protonemal morphogenesis in mosses III. The perennial gemmiferous protonema of Rhizomnium punctatum (Hedw.) Kop. Journal of Bryology 18: 13-26.
Duckett JG, Matcham HW (in press). Studies of protonemal morphogenesis in mosses. VII. The perennial rhizoids and gemmiferous protonema of Dicranella heteromalla (Hedw.) Schimp. Journal of Bryology (in press).
Goode JA, Alfano F, Stead AD, Duckett JG. 1993a. The formation of aplastidic abscission (tmema) cells and protonemal disruption in Bryum tenuisetum Limpr. is associated with transverse arrays of microtubules and microfilaments. Protoplasma 174: 158-172.
Goode JA, Duckett JG, Stead AD. 1993b. Redifferentiation of moss protonemata: an experimental and immunofluorescence study of brood cell formation. Canadian Journal of Botany 71: 1510-1519.
Mr G. Stark (Joint Nature Conservation Committee, Peterborough): The Lower Plant Biodiversity Register.
At the end of last year I began work on the Lower Plant Biodiversity Register project. The project extends JNCCs interest in lower plant conservation. My initial brief was to collate data on lower plants in order to develop a system for the identification and ranking of sites important for their lower plant interest. Our ideas have evolved over the past year, and considerable thought has gone into what kind of information we would like to collect, how to store this information and how we can use this information to the benefit of lower plant conservation.
Bryophytes and stoneworts have been a testing ground for the project. To date I have made entries for some 2500 populations of Red Data List bryophytes based on records in the BBS Atlas database at the Biological Records Centre. Many of these populations have not been seen for some time. Entries in the Register are not the same as records held in the Atlas database; a Register entry, such as ‘Cratoneuron decipiens on Ben Lawers’ or ‘Cheilothela chloropus at Berry Head’, will relate to a number of Atlas records. We also hope to make Register entries more comprehensive, with details of habitats and threats and notes on occasions where a species has not been refound. Over the forthcoming months I will be adding to these entries from forms returned by BBS recorders, comments made on the original records cards and various surveys and special projects carried out by the county conservation agencies.
An obvious way in which the Register can be used is to disseminate information about populations of rare lower plant species. The work of the country conservation agencies (English Nature, Scottish Natural Heritage and The Countryside Council for Wales) includes casework relating to potential threats to nature conservation sites, planning applications or changes on SSSIs for example. Site managers and conservation officers often do not have specialist bryophyte expertise, with notable exceptions! We intend to make the information held on the Lower Plant Biodiversity Register available to these staff, either through regional reports or possibly computer copies of the Register itself. We see the Register as sitting at an interface between the statutory conservation agencies and the specialist knowledge of societies like the BBS. By making information about Red Data List bryophyte populations more easily available we hope to encourage their consideration by non specialists.
In addition to disseminating information the Register will be used to get an overview of lower plant conservation. An example of this is the occurrence of Red Data List bryophytes on National Nature Reserves (NNRs). About a half of the 220 Red Data List bryophytes had at least one occurrence on a National Nature Reserve. Occurrence on a NNR is incidental, since populations of lower plants were not a consideration in the designation of NNRs. Note that this is not a complete picture of protection since species may occur on other protected sites (SSSI or local nature reserves) or have species protection under the Wildlife and Countryside Act. A few NNRs have populations of many species (Ben Lawers NNR 42, Cairngorms NNR 21 and Caenlochan NNR – all extensive Scottish upland sites) but the majority have one or two species. We compared representation of species on NNRs with their habitat and life strategy.
The picture is much as we had expected although interestingly it contrasts with that for invertebrate species for which there is a higher representation of Red Data List species on protected sites in SE England. In the case of rare invertebrates in regions like East Anglia the few areas of good habitat are mostly protected, have been intensively studied and have a higher number of rare species than reserves in the uplands. This is less the case for Red Data List bryophytes, since rare bryophytes in regions like East Anglia tend to be species of marginal habitats such as exposed mud or arable fields, sites unlikely to have statutory protection as NNRs.
Protection of sites may suit some species but it is not appropriate for all – those species with the life strategy of shuttle species being a case in point. Further, site based protection does nothing to enhance the environment in which most of us live most of the time. Discussion of wider countryside conservation is currently dominated by birds, where site based protection is often limited because of the large amount of land which would be required for it to be effective. A similar argument could be put for bryophyte species which move around a lot. These species do not require for extensive tracts of land to be designated as reserves, but would benefit from sympathetic land management practices in a working landscape. In the future we hope to use the Register to make recommendations which will benefit bryophytes growing outside of protected and managed reserves.
Dr E.V. Watson (Cleeve): Sixty years in bryology.
Under the title ‘Sixty years in Bryology’, Dr Watson recalled his first tentative steps, taken in student days at Edinburgh in the nineteen thirties, when he received significant help and encouragement from Mr William Young, who had been a founder member of the Moss Exchange Club back in 1896 and was busy reorganising bryological material in the Herbarium of the Royal Botanic Garden, Edinburgh.
Reference was made to the exploratory visits paid by some members of Edinburgh University Biological Society to Barra in June 1935 and in summer 1936 when it fell to Dr Watson to investigate, among other things, the mosses. Help in identification was received from long-standing BBS member, J.B. Duncan of Berwick-on-Tweed. Much valuable experience was gained and these studies culminated in a paper ‘The mosses of Barra, Outer Hebrides’ in Transactions of the Botanical Society of Edinburgh 32, 1939.
To a certain extent, a ‘fresh start’ was made in the spring of 1946 when the opportunity was seized not only to join the BBS but to attend the Meeting of the Society held at Appleby at that time. As a direct outcome of taking these two steps, Dr Watson found himself, by the autumn of that year, on the staff of the Botany Department at the University of Reading and Bibliographer of the British Bryological Society; the first to last for 33 years, the second for 25!
Soon after arrival at Reading a big new opportunity arose when Professor Tom Harris made the suggestion that a simple book on bryophytes might be written, expressly aimed at beginners. The seed had been sown from which British Mosses and Liverworts was to grow. This ‘growth’ took some time and Dr. Watson expanded a little on some of the phases of that process. He emphasised the generous help he received throughout from Professor Paul Richards. He enlarged on some of the misgivings he had about the book and his delight and relief when it was well received on its appearance in April 1955. One innovation was a key which took one direct to species. Another was a field key, to the most prominent and easily recognisable species, in a folder at the back. Key making was much ‘in fashion’ at the time at Reading, Dr F.B. Hora being deeply involved in making his ‘Field Key to Common British Mushrooms and Toadstools’.
There followed what might be called the ‘middle years’, i.e. roughly the period from the mid-nineteen fifties to the mid-nineteen seventies, but a digression was made to recall certain incidents, customs and outstanding personalities of 40 years ago. Up to about 1956 the daily excursions on Spring Field meetings were by coach. This afforded one the opportunity to make interesting new friendships, while a tea-time break at a hotel or restaurant enabled people to talk over some of the finds of the day. Two people who played key parts, not only on field trips but in the affairs of the society as a whole, were E.C. Wallace, who had been our tireless secretary from 1946 onwards, and E.F. Warburg, who had, it seemed, an encyclopaedic knowledge and a keenness of eye that nobody else could match.
Two characteristic features of those days (40 or so years ago) were (1) that vice-counties were the sole geographic units in terms of which distribution was studied and (2) an annual event known as the ‘Exchange and Distribution’ whereby material (much of it from abroad) was assembled by the secretary and in due course distributed to interested members. It was invaluable for anybody attempting to build up a reference herbarium.
Reference was then made to the work that had been involved in holding office as Bibliographer and thus preparing, year after year, the contribution entitled ‘Recent bryological literature’; and it was pointed out how this work enabled Dr. Watson to consider acceptance when, in 1960, an invitation came from Professor Munro Fox to write a book in Hutchinsons University Library. The outcome was Structure and Life of Bryophytes, which was published in 1964. A somewhat different plan was adopted from that found in any bryophyte text that had gone before. There were difficulties, not least the strict limits to the length of the book and a format which precluded anything like satisfactory illustrations. The author’s period as Bibliographer (1946-71) just allowed him to stay reasonably in touch with the advancing stream of literature until a second edition had been prepared, with its greatly extended list of references.
Playing a quiet ‘background role’ as one of the Society’s panel of ‘referees’ was something that had been going on now for 40 years. It was interesting and at times challenging work being referee for Pohlia, Bryum and Philonotis (and seven other less difficult genera). The ‘referee’s nightmare’, of a great avalanche of material being suddenly unleashed upon one, had not so far occurred. Considerable problems could be posed occasionally, for example when two species chose to grow intimately entwined with one another; or again when one was asked to give a verdict on a minute specimen which had been firmly attached to a piece of card with the best Victorian glue by a bryologist over 100 years ago. An occasional moment of light relief would come when the plant sent in as Bryum sp. turned out to be Funaria hygrometrica!
It had to be admitted by the author of this contribution that the last fifteen to twenty years had been a time when he had played a greatly diminished part. For the BBS as a whole, however, this had been a time of burgeoning activity on many different fronts.
Accordingly, for the final part of this review of his ‘Sixty years in Bryology’ Dr Watson turned briefly to some of the directions in which both the subject as a whole and BBS activities had been fast expanding. Reference was made to the more complex and demanding role of the Bibliographer today and the increased volume of contemporary bryological literature. He emphasised the many sources to be tapped now by the young enthusiast in contrast to the situation 60 years ago.
Finally, he saw fit to compliment fellow members on some of the outstanding achievements of recent times. Most notable, surely, was the culmination of the ‘mapping scheme’ – embarked upon 34 years ago – in the publication of the three handsome volumes of the Atlas of the Bryophytes of Britain and Ireland’. Another encouraging development had been a closer collaboration with bryologists and bryology overseas.
Mr D.G. Long (Royal Botanic Garden, Edinburgh): Bryological exploration of Nepal.
Nepal is a Himalayan kingdom of 54,000 square miles dominated by the Himalayan chain of mountains with several of the world’s highest peaks. In altitude it ranges from 60 m up to 8848 m and supports a wide range of habitats from subtropical forest to alpine desert. The climate is monsoonal with heavy summer rains. Rainfall is highest in the east, declining westwards with quite arid interior areas in the west. The high rainfall leads to a high treeline (4000 m or more) in the east.
Nepal remained virtually unexplored bryologically before 1950. The earliest collectors, Buchanan, Gardner and Wallich (early 19th century) were restricted in their movements to parts of central Nepal and made only limited collections. These specimens came to Britain and were worked on by W.J. Hooker and W.H. Harvey. J.D. Hooker was the first botanists to explore the wetter but richer eastern Nepal in 1848. His collections were researched by Mitten. The century following this saw virtually no bryological activity in Nepal, but since 1950 most parts of the country have been at least partly explored.
The author led a botanical expedition to East Nepal in September/October 1991, to the Barun Khola valley, Makalu area, Hatiya and Milke Danda ridge (the region east of the Everest range). The last of these areas had been explored by Japanese bryologists in the 1970s, and found to be very rich with rarities such as Takakia. The expedition was funded jointly by the Royal Botanic Garden, Edinburgh and private sponsors, and the team included a Nepalese liaison botanist from Kathmandu.
Transport was by a Twin Otter plane to the airstrip at Tumlingtat in the Arun Valley, thereafter we walked with a team of Sherpa guides and porters. Collecting was primarily of vascular plants but substantial bryological collections were possible. Drying of specimens was effected by kerosene heaters in a drying frame, and dry specimens were sealed in polythene bags and carried by porters.
Many threats to the rich bryoflora of East Nepal were in evidence: overpopulation is the greatest threat as it forces poorer villagers into the steep inner valleys where primary forest is degraded by felling, burning and grazing. This land is of very low agricultural potential. The resulting secondary scrub is of low bryological interest in comparison to the primary rain forest. Trekking and tourism are recent threat; they lead to a ‘honeypot’ effect along footpaths where villagers settle and open teashops and rest-houses with consequent stresses to the vegetation.
In the Arun Valley north to Num only pockets of primary forest survived. Nevertheless many interesting bryophytes were seen in disturbed and cultivated areas and pockets of forest. Two Asterella species were frequent: A. mussuriensis and A. khasyana. Bryowijkia ambigua was a distinctive epiphyte. On shady paths Conocephalum japonicum was collected. At Num the Arun river gorge was crossed, followed by a gradual ascent through temperate forest zones with a steadily improving bryoflora. Abies densa/Rhododendron forest clothed the slopes below the Shipton La pass with robust ground mosses such as Actinothuidium hookeri, Rhodobryum giganteum, Breutelia setschwanica and Paraleucobryum enerve. Rotten logs were richly clothed in liverworts such as Lophozia setosa and Delavayella serrata.
The Shipton La pass (4130 m) was a rich alpine habitat with wet cliffs with extensive Takakia ceratophylla and block scree with Anastrophyllum joergensenii c. spor. and many other Hepaticae. The descent on the north side was back into dense Rhododendron forest in the Barun Khola valley. The valley turned out to have extensive outcrops of calcareous schist rocks and exceptionally rich bryophyte assemblages: some of these supported some of the rare European Alpine calcicoles such as Cirriphyllum cirrosum, Blindia caespiticia, Encalypta alpina, Campylium halleri and Meesia uliginosa. Two thalloid liverworts new to science were found here: Asterella grollei and Aneura crateriformis. Just as interesting was the first Sphaerocarpos for E. Asia: S. stipitatus, known from Chile, South Africa and Portugal.
Continuing up the Barun Khola, the rain shadow effect soon dramatically changed the vegetation to dry xerophytic scrub and scree. The bryophytes were much less rich, but still of interest: e.g. the abundance of Rhytidium rugosum. Other rarities were Andreaea frigida and the cleistocarpous member of Splachnaceae, Voitia nivalis. On Makalu itself we climbed to 18,000 feet where a few bryophytes were still present.
The return journey took us to the remote village of Hatiya on the Tibetan border where magnificent surviving forest of hemlock (Tsuga dumosa) were of great interest. Here was found Scaphophyllum speciosum, Geocalyx graveolens and Acrobolbus ciliatus, the first new to Nepal and a significant extension from its other localities in Bhutan and Taiwan. Next we ascended the Milke Danda ridge, an important yak-herding route with severe degradation of the Rhododendron forest in places. Notwithstanding, some good finds were made including Campylostelium saxicola new to the Himalaya and both Tetrodontium brownianum and T. repandum.
The journey back to Kathmandu involved a very long bus journey, during which one of the parcels of bryophytes mysteriously disappeared. In spite of this, over 2000 collections were made including several taxa new to science and others new to Nepal. There is no doubt of the richness of East Nepal’s bryoflora. Perhaps most interesting is the discovery that some of our own ‘Northern Atlantic’ liverworts are much more extensive in the Himalaya than in Europe, e.g. Anastrophyllum donianum and A. joergensenii, Bazzania pearsonii and Pleurozia purpurea.
Mr B.J. O’Shea (London): Malawi bryophytes and the checklist of sub-Saharan African mosses.
The collections from the BBS Tropical Bryology Group 1991 expedition to Mount Mulanje, Malawi, are now being processed at an increasing rate, and approximately 21% (1600 mosses and 800 hepatics) are now identified or with experts for identification. 37 experts were assisting members of the expedition team in identification. The 4500 collections were expected to yield about 11250 taxa, at 2.5 taxa per collection. Of the 212 different taxa so far identified, 57% were new to the known flora of Malawi. It was estimated that two to three years more would be needed to complete the work.
Work on the Malawi flora had identified the need for a checklist of sub-Saharan African bryophytes to supplement and integrate the rather poor existing documentation of the bryophyte flora. The hepatic checklist was being pursued by Martin Wigginton, but although work on the moss list was not yet complete, it was now possible to derive some preliminary conclusions on the overall number of taxa on the continent, and the likely effect on this of taxonomic revisions. By looking at revised groups (Campylopus, Leptodontium, Neckeropsis, Porothamnium/Porotrichum, Rigodium, Sphagnum, Thuidium s.l.) and unrevised groups (Isopterygium, Leucoloma, Macromitrium, Pilotrichella, Racopilum, Sematophyllum, Schlotheimia, Taxithelium, Vesicularia, Zygodon) as well as those in process of revision (Calymperes, Fissidens), it was shown that many groups with large numbers of apparent endemics may not have endemics at all, and were the result of poor taxonomy of the past, when large numbers of unnecessary taxa were described. Useful metrics for genera with large numbers of species seemed to be the number of countries in which taxa occurred (ca. 2 for unrevised vs. 8 for revised genera), and the number of taxa occurring in only one country (ca. 50% for unrevised and 25% for revised genera). The dangers of making such generalisations without careful study of the genus in question was emphasised: Archidium was given as an example of a revised genus that displayed the ‘unrevised’ characteristic of thinly distributed species, but which in that case were genuinely endemic species. Nevertheless, it was important to remove the ‘noise’ of unnecessary taxa before it was possible to make specific statements on diversity and endemism in African mosses, and thus allow appropriate conservation procedures to be defined. Our poor knowledge of the African flora was emphasised by further information from the African moss flora database – 32 of the 50 countries and islands included in the list had fewer than 100 taxa recorded, and 11 had fewer than 10 – which underlined the need for many more expeditions such as the one to Malawi to improve our knowledge, and the urgent need for training of local bryologists.
Field excursion to Roundton Hill, Todleith Hill and the River Onny, 25 September 1994
The morning was spent in the vicinity of the Montgomery Wildlife Trust Reserve of Roundton Hill, just on the Welsh side of the border, a small rocky and grassy hill with wooded fringes on a substrate of dolerite. Tortula canescens has been recorded there in the past. The party split into two, one group examining Roundton Hill itself, with another going to the neighbouring Todleth Hill, which is less well-known than Roundton and more wooded.
A not-unexpected assemblage of predominantly calcifuge species was recorded on Roundton Hill, including Andreaea rothii, Cynodontium bruntonii, Hedwigia stellata (recently distinguished from H. ciliata, which was not found here) and Pterogonium gracile on rocky crags, with Lophozia bicrenata and Scapania compacta in rock crevices. Tortula canescens was searched for but unfortunately not found. Some members attempted to distinguish between the varieties of Hypnum lacunosum, explained the previous day, in the field. There were a few more calcareous outcrops with Encalypta streptocarpa, Fissidens cristatus and Tortella tortuosa, with Climacium dendroides in short turf nearby. Chris Walker found Grimmia laevigata, the first record from Roundton for some years. In the swirling mists and wind at the summit of the hill, it was almost possible to imagine oneself on a Scottish mountain!
The other party had an interesting morning on Todleth Hill, the extra shade and humidity of the site proving more rewarding than the relatively bare slopes of Roundton, and providing an interesting mixture of lowland and upland species. Notable finds included Amphidium mougeotii, Cirriphyllum crassinervium, more Hedwigia stellata, Racomitrium affine, Barbilophozia barbata, Lejeunea cavifolia and Reboulia hemisphaerica. The oceanic liverworts Lejeunea lamacerina, Saccogyna viticulosa and Scapania gracilis were all recorded, here at the eastern limits of their distribution in the Welsh borders.
After lunch, and a small amount of confusion en route caused by a Ron Shoubridge look-alike eating lunch in his car, the remaining members of the party returned to the English side of the border (Shropshire) to examine the characteristic riverine bryophyte communities in the flood zone on the banks of the River Onny, near Cheney Longville. In the gathering autumnal dampness, species such as Leskea polycarpa and Orthotrichum rivulare were seen on riverside trees, as well as very nice stands of Scleropodium cespitans. Pseudephemerum nitidum and Fossombronia wondraczekii were recorded from muddy banks and several elder trees had reasonable epiphytic communities, with Bryum flaccidum, Orthotrichum spp., Zygodon viridissimus, Frullania dilatata and Radula complanata. Tom Blockeel and Jean Paton explored another stretch of the river, where they found Tortula latifolia and Porella cordaeana, and examination of adjacent stubble fields yielded Ephemerum serratum var. minutissimum, Riccia glauca and R. sorocarpa.
Nick Hodgetts