Meeting report

Bryological symposium

Through the kind invitation of Dr J.R. Edmondson, we were privileged in holding this meeting at Liverpool Museum, the history and future plans of which were briefly reviewed by Mr E.F Greenwood (Assistant Director) in his welcoming address. Time allowed only a brief excursion into the public galleries but it was clear that, in presenting images of Liverpool’s past achievements as well as of more general matters, the museum is closely in tune with the public of to-day, who were there in force.

Some of Liverpool’s seafaring tradition was brought into the lecture room by one of the speakers in describing bryophyte collections from the Caribbean. Another speaker described the fascinating BBS museum exhibit, which many of us have not yet been able to see, and thus showed us the Society’s attempts to extend members’ enthusiasm for bryophytes to a wider public. Indeed, it is a measure of the continuing and active bryological interests of BBS members that, in a year when a three-day symposium on bryophyte ecology had already been held, it was still possible to draw up a programme of important papers. Although the remaining five all had ecological implications, they were nevertheless wide-ranging in their approach. One speaker reported a surprising variety of mycorrhizal associations with liverwort flagella, which were themselves shown to be of greater extent than previously supposed, and another explored crucial aspects of nutrient uptake experimentally in mosses.

The other three papers were all concerned with the impact of human activity on the environment and on bryophytes. An intensive study, by one of the speakers, of the physiological effects of sulphur dioxide on Sphagnum was shown by another to be closely related to the extensive use that is now being made of bryophytes in assessing levels of pollution. This evidence of bryophytes as victims as well as detectors of pollution was well complemented by a later paper describing the diversity of problems faced by conservationists and some of the ways in which they have been overcome. The following are abstracts of these papers supplied by their authors.

Dr J.W. Bates (Imperial College at Silwood Park): “The use of fertilizer experiments to study nutrient absorption and utilization by bryophytes.”

There is a widespread belief that bryophytes obtain nutrients principally in pulses from precipitation. Field experiments involving nutrient application to Pseudoscleropodium purum and Pleurozium schreberi in Windsor Forest, Berkshire were designed to examine the ability of mosses to retain nutrients from dilute solutions. K and Ca were readily adsorbed onto the cell walls of P. purum but were quite rapidly leached away. Added K did not pass into the protoplasts appreciably but P was avidly absorbed although it too was eventually lost from the green tissues. Displacement of Mg from the cell walls, as a result of Ca addition, led to a decrease in the Mg concentration of the protoplasts suggesting that Mg uptake involves a preliminary exchange step. The results indicate that, for K at least, P. purum is little influenced by external supply perhaps pointing to efficient internal recycling of nutrients. When CaCO₃ was applied to the mineral soil below carpets of Pleurozium schreberi, substantial Ca accumulation was observed in the young shoot apices, indicating that the importance of nutrient supply from the soil to bryophytes may have been underestimated by earlier workers.

Mr R. Baxter (University of Manchester): “The responses of Sphagnum cuspidatum to atmospheric pollutants, particularly SO₂.”

Ombrotrophic mires are amongst the most sensitive ecosystems to atmospheric pollution because they rely on an atmospheric source of elements and are usually dominated by bryophytes (Lee, Press, Woodin & Ferguson, 1987).

In the southern Pennine mires of England, extensive modification of the blanket peats and communities has occurred since the Industrial Revolution, with the virtual elimination of the once dominant Sphagnum cover. This change is largely the result of the long history of atmospheric pollution (notably of sulphur dioxide) in the region (Tallis, 1964; Ferguson & Lee, 1983). Today ombrotrophic Sphagnum species such as S. cuspidatum, are rarely to be found on the bog surface in the region. These simple aquatic plants have leaves one cell thick and lack cuticles, thus the chlorophyllose cells are continuously exposed to changes in the chemical composition of the pool water which might result from atmospheric pollution episodes.

In less polluted regions such as N. Wales, Sphagnum species still dominate the blanket mires. It is thought that the small populations of ombrotrophic Sphagnum species that occur in the S. Pennines today may be relict populations of the former extensive Sphagnum cover, and there is some evidence that plants from these populations may be more resistant to sulphur dioxide than those from populations in less polluted regions.

The effects of the bisulphite ion (HSO₃-) (a major solution product of sulphur dioxide) on the growth and certain aspects of the physiology of S. cuspidatum plants from a polluted S. Pennine and an ‘unpolluted’, N. Wales population were carried out as a basis for understanding the intraspecific differences in tolerance to this pollutant. Shoots of S. cuspidatum from both sites were grown in the laboratory and exposed to 0.1mM bisulphite in the growth medium. It was found that bisulphite application produced significantly less than maximum growth in Sphagnum from both sites. This effect was far greater, however, in the material taken from N. Wales. The effect of bisulphite on photosynthesis in Sphagnum from both populations was also monitored. Photosynthesis declined steadily with time in the moss from N. Wales. In contrast, bisulphite initially stimulated photosynthesis in the Sphagnum from the polluted S. Pennine site. Observation of the bisulphite-treated moss samples 10 days after the initial addition of bisulphite showed that the moss from N. Wales had been completely bleached, whereas the S. Pennine Sphagnum appeared unchanged, and apparently healthy. Thus there was indeed a very pronounced intraspecific difference in the response to, and ability to survive, the bisulphite treatment.

It had been believed for some time that the difference in response of the two Sphagnum populations to sulphur dioxide pollution lay in the ability of the S. Pennine moss to more rapidly metabolise the bisulphite to the less phytotoxic sulphate species. In the present investigation, the mode of avoidance of phytotoxic attack in the moss from the grossly polluted S. Pennine site was found to be the ability to promote a rapid oxidation of the bisulphite to less toxic sulphate species in the solution bathing the moss, i.e. external to the plant. This facilitates the prevention of entry of the toxic bisulphite into the cell environment. This promotion of the oxidation rate of bisulphite to sulphate was found to result from the presence of high concentrations of transition metal ions such as Fe³+, Cu²+, and Mn²+ present on the cation exchange sites of the moss (for details on the phenomenon of cation exchange in Sphagnum see Clymo, 1963). The high concentrations of iron, manganese and copper associated with the S. Pennine moss result from the increased atmospheric deposition of these metals since the time of the Industrial Revolution, and which are present in the S. Pennine peat today as a legacy of those past pollution events. At the Welsh site, relatively remote from industrial activity, there is very little metal contamination of the bog surface, hence very little iron, manganese, or copper is associated with the Sphagnum plants. Thus, on exposure of the moss to bisulphite no catalytic promotion of the oxidation of this chemical species is effected, and it persists in solution for up to 24 hours. During this time it is able to pervade the cell environment and results in eventual death of the moss. (For further details see Baxter, Emes & Lee, in press.)

In recent years the emissions of sulphur dioxide have dramatically declined (see Ferguson & Lee, 1983). This has partly been as a result of the Clean Air Acts of the 1950’s. Today there is evidence of an increase in the nitrogen component of atmospheric deposition on ombrotrophic bogs. This has resulted from the change from the burning of coal to the burning of oil, and from the combustion engine. Evidence suggests that this increased nitrogen deposition on the surfaces of mires close to industrial regions (such as in the S. Pennines) may be deleteriously affecting the growth of Sphagnum species (Lee, Press, Woodin & Ferguson, 1987). Work is continuing at Manchester into the effects of this increased nitrogen on the upland blanket bogs of the S. Pennines.

References

Baxter, R., Emes, M.J. & Lee, J.A. Effects of the HSO₃– ion on growth and photosynthesis in Sphagnum cuspidatum Hoffm. New Phytol. (in press).

Clymo, R.S. (1963). Ion exchange in Sphagnum and its relation to bog ecology. Annls Bot.(N.S.) 27, 309-324.

Ferguson, P. & Lee, J.A. (1983). Past and present sulphur pollution in the S. Pennines. Atmospheric Environment 17, 1131-1137.

Lee, J.A., Press, M.C., Woodin, S.J. & Ferguson, P. (1987). Responses to atmospheric deposition in ombrotrophic mires in the U.K. In: T.C. Hutchinson & K.M. Meema (eds.) Effects of atmospheric pollutants on Forests, wetlands, and agricultural ecosystems. Springer Verlag, Berlin.

Tallia, J.H. (1964). Studies on southern Pennine peats. III. The behaviour of Sphagnum. J. Ecol. 52, 345-353.

Dr M.A.S. Burton (Monitoring and Assessment Research Centre, London): “Monitoring contaminants in bryophytes: regional and baseline studies”.

Bryophytes have been used for some years to monitor the deposition of contaminants in the vicinity of industrial and urban sources of emission to the atmosphere or discharges to freshwater. The widespread distribution of bryophytes in both temperate and tropical localities has led to their use in monitoring the distribution of contaminants on a regional scale and to detect temporal trends in deposition patterns over large areas of land. Bryophytes intercept and retain many contaminants and data have been collected for metals and radionuclides in particular. Recently organochlorine pesticide residues have also been recorded in samples from agricultural areas and in antarctic localities. Samples can be collected from many sampling points at low cost compared with alternative methods and from remote localities where it would be impractical to use instrumental methods at least for preliminary surveys. Radionuclides retained by moss samples at northern latitudes following the testing of nuclear weapons in the 1960s reflected the extent of testing carried out in different years; data have also been collected after the accident at the Chernobyl reactor in 1986. Species differences in habit and morphology affect retention of contaminants and regional surveys generally utilise the same species. In the Nordic countries the practicality of implementing a programme to monitor regional metal deposition patterns by analysis of moss samples has been demonstrated. Temporal trends have also been evident, with the lower lead content of petrol. Baseline concentrations of a number of contaminants in mosses at remote locations form part of Integrated Background Monitoring programmes in both temperate and tropical countries. Despite some differences in methodology and species collected, similar concentrations of some metals have been recorded in very different habitats and provide data for comparison with impacted areas.

Prof. J.G. Duckett, Prof. K.S. Renzaglia*, K. Pell and A. Russell (Queen Mary College, London and *East Tennessee State University, U.S.A.): “The biology of underground organs in the Jungermanniales.”

It has long been stated that northern hemisphere hepatics have only rhizoids growing through the substratum. The only well documented exceptions are the so called “roots” in Calobryales (Grubb, 1970) the almost leafless subterranean axes in some antipodean Cephaloziineae and Lepidoziaceae (Schuster, 1980) and the completely subterranean Cryptothallus. A recent survey of British hepatics (Pocock & Duckett, 1985) revealed that several genera characteristic of peat bog communities (Kurzia, Lepidozia, Cladopodiella, Cephalozia, Odontoschisma) possess extensive systems of underground axes. These produce numerous rhizoids many of which have swollen, fungus-containing tips. To understand further the significance of these subterranean systems we have begun electron microscope studies on their fungal associations (Duckett & Renzaglia, 1988) and regeneration experiments both on natural substrata and in culture. Initially confined to peat bog communities (Duckett & Clymo, 1988) the work has now been extended to a range of habitats in both Britain and the Malaysan tropics. The results are shedding new light on morphogenesis, gravitropism and assimilate translocation in liverworts and suggest that these plants are much more important components in several major vegetation types than recognized hitherto.

In initial experiments (Duckett & Clymo, 1988) liverwort regeneration was investigated on horizontal slabs cut at 2-3 cm intervals from peat cores from an actively growing Sphagnum surface and one which had previously been cut for peat. Regeneration was limited to the surface in species lacking underground axes (Lophocolea, Barbilophozia, Lophozia, Calypogeia, Riccardia,) whilst species with subterranean systems produced new shoots from depths down to 24-30 cm. Subterranean axes are probably the main organs of perennation in these hepatics. Their presence is a likely explanation for the rapid colonization by such hepatics of decaying Sphagnum or of peat surfaces following fires.

Subterranean axes are not merely confined to peatlands, but have now been detected to depths of up to 10 cm in rotten logs (Lepidozia reptans,) 20 cm in humus-rich soil woodlands in the west of Ireland (Cephalozia spp., Kurzia spp., Telaranea nematodes) and 30 cm in hummocks of Leucobryum (Bazzania trilobata, Odontoschisma sphagni). Slabs cut from all these locations show abundant liverwort regeneration to the depths given above. Most striking however, is the discovery that numerous members of the Lepidoziaceae in Malaysia (Genting and Cameron Highlands, Mount Kinabalu) produce subterranean axes extending to depths of up to 1.5m in peaty substrata in upper montane rain forest. By contrast, when growing on sandstone rocks in Britain the subterranean axes produced by Kurzia spp., Cephalozia spp., Odontoschisma denudatum and Bazzania trilobata rarely exceed lcm in length.

Whereas in the majority of Jungermanniales the fungal symbionts are basidiomycetes which form a continuous strand in the ventral cells of the stems, those forming associations with subterranean axes are confined to the rhizoids and are ascomycetes – identified by the presence of simple septa and woronin bodies. Each rhizoid, or fascicle of rhizoids, is infected independently and a continuous strand of fungus-containing cells is absent. The absence of prokaryotic endosymbionts from the axes indicates that the claims of nitrogen fixation by liverworts such as Kurzia (reviewed by Schuster, 1966) were almost certainly due to the presence of contaminating surface cyanobacteria.

The ultrastructure of the associations varies greatly between genera. In Cladopodiella, but not other genera, the fungus forms a pseudoparenchymatous sheath in a thick layer of mucilage round the tips of swollen rhizoids, which elongate after infection. Development of swollen rhizoid tips precedes fungal infection in Lepidozia, Kurzia and Telaranea. In Bazzania fungi invade rhizoid initials situated along the base of rudimentary leaves and in Odontoschisma fungi are most numerous in papillate cortical cells. Hyphae penetrating through the basal walls of the rhizoids in Cladopodiella, Cephalozia and Odontoschisma are ensheathed by ingrowths of liverwort wall material similar to those in ericoid mycorrhizas. These different patterns of fungal infection suggest their independent evolution in the various genera.

The gross morphology of the subterranean axes is similarly varied. British and Irish Lepidozias, Kurzias, Telaranea and almost all of the 30 tropical Lepidoziaceae so far examined produce fascicles of rhizoids from the bases of widely spaced rudimentary leaves. In Cephalozia the leafless subterranean axes bear widely spaced mucilage papillae dorsally and rhizoids ventrally. Cladopodiella and Odontoschisma produce radially symmetrical leafless axes with rhizoids throughout their circumference. In some tropical Lepidoziaceae lateral branches of the subterranean axes bear antheridia or archegonia several cms below the surface.

Not only do the subterranean axes regenerate from cut surfaces of their natural substrata but they also grow when isolated in sand, water or agar cultures. When kept in the dark they retain their wild morphology but on exposure to light regenerate into leafy shoots which produce a sequence of appendages from mucilage papillae through juvenile leaves to adult leaves. Experiments on vertical agar plates kept in the dark reveal the apices to be gravitropic.

Loss of this response in the light is correlated with the disappearance of subapically located amyloplasts which appear to act as geoperceptive particles. Whatever the medium or light regime, in culture new growth from the subterranean axes is invariably fungal free. The number of lateral branches produced in culture by Odontoschisma sphagni and Bazzania trilobata is the same in decapitated as in intact shoots whereas removal of the apices of moss shoots leads to a massive increase in lateral bud formation.

When considered in the context of assimilate translocation from the surface the vertical extent of the subterranean axes appears very remarkable if not highly improbable. The fact that the axes comprise but a central group of slightly elongated parenchyma cells surrounded by isodiametric cortical cells, with no suggestion of differentiation in relation to conduction, appears to rule out effective translocation over several cms. A key to this problem may lie with the ascomycetous fungal associates. The suggestion that the hepatics may be acting as alternative hosts to ericaceous mycorrhizas (Duckett & Clymo, 1988) thus allowing the possibility of lateral movement of assimilates may explain how delicate axes reach depths that initially seem unlikely. That these liverworts are either partial parasites (receiving organic matter indirectly from Ericaceae via their fungi) or partial saprophytes (assimilates from the breakdown of organic matter in the substratum) was a hypothesis developed initially from observations on temperate species. It appears even more credible in the tropical context. Whereas less than 20% of British Jungermanniales have rhizoidal fungi the corresponding figure for montane forests in Malaysia may be as high as 80-90%. Such forests boast some of the world’s richest ericaceous floras (Luping et al., 1978). Nor should Ericaceae be considered as the only alternative hosts for the rhizoidal fungi. Our most recent finding is that the majority of hymenophyllaceous ferns (Hymenophyllum and Trichomanes) from both temperate and tropical regions possess swollen and branched root hairs associated with fungi.

References

Duckett, J.G. & Clymo, R.S. (1988). Regeneration of bog liverworts. New Phytol. 110, 119-127.

Duckett, J.G. & Renzaglia, K.S. (1988). Symbiotic ascomycetes in the rhizoids of jungermannialian liverworts. Am J. Bot. (in press).

Grubb, P.J. (1970). Observations on the structure and biology of Haplomitrium and Takakia, hepatics with roots. New Phytol. 69, 303-326.

Luping, D.M., Wen, C. & Dingley, E.R. (eds.) (1978). Kinabalu, Summit of Borneo. Sabah Society Monographs.

Pocock, K. & Duckett, J.G. (1985). On the occurrence of branches and swollen rhizoids in British hepatics: their relationships with the substratum and associations with fungi. New Phytol. 99, 281-304.

Schuster, R. M. (1966). The Hepaticae and Anthocerotae of North America East of the 100th Meridian. Volume 1. Columbia University Press.

Schuster, R. M. (1980). Studies on Hepaticae, LIV-LVIII. Kurzia V. Mart. (Microlepidozia (Spr.) Joerg.) Megalembidium Schust., Psiloclada Mitt., Drucella Hodgs. and Isolembidium Schust. J. Hattori bot. Lab. 48, 337-421.

Acknowledgement. The observations on the Malayan hepatics were made possible by a study grant to J.G. Duckett from the Royal Society.

Dr J.R. Edmondson (Liverpool Museum): “Bryophyte collections made during the Caribbean voyage of the ‘Argo’.”

The Reverend Henry Hugh Higgins (1814-1893) made a tour of the Caribbean in 1876 as a member of the “Argo Expedition” whose primary aim was to obtain living specimens for a menagerie in Shropshire. Travelling on the Royal Mersey Steam Yacht “Argo” he visited Dominica, Grenada, Jamaica, Martinique and Trinidad as well as Venezuela and Madeira, and collected a total of 289 mosses, liverworts, lichens and ferns. His collection was donated to Liverpool Museum with which Higgins was closely connected as a voluntary curator and member of the Museum Committee. Higgins was also Chaplain of Rainhill Asylum and a noted amateur palaeobotanist.

The 47 Caribbean mosses collected by Higgins were recently revised by Dr William Buck, New York Botanic Garden, for his Moss Flora of the West Indies. They include the type of Hookeria higginsiana Bescherelle ex Higgins. The scientific name of this moss was validated by Higgins in the appendix to his memoir, “Notes by a Field Naturalist in the Western Tropics”, published in Liverpool in 1877. Hookeria higginsiana, described from above Roseau, Dominica, is now regarded as a synonym of Hookeriopsis leiophylla (Besch.) Jaeger.

Dr S.R. Edwards (Manchester Museum): “What they wouldn’t let us put in the exhibition.” A SECRET GARDEN: THE HIDDEN WORLD OF MOSSES AND LIVERWORTS

A Travelling Exhibition sponsored jointly by the British Bryological Society, City of Bradford Metropolitan Council, and Yorkshire and Humberside Museums’ Council; first opened to the public on December 5th, 1987, at Cliffe Castle Museum, Keighley, and now travelling.

Introduction

The paper read at Liverpool was originally entitled “What they wouldn’t let us put in the Exhibition”, because so much had to be left out; indeed about 86% of the submitted material was omitted, and it was felt that members should have an opportunity to see at least some of the discarded bryologia.

However, it was clear that most of the BBS membership had not yet seen the Travelling Exhibition at all (which at that time had only visited Keighley and Manchester). Also in the time available at Liverpool, it would not have been possible to cover a fraction of the material in the Exhibition, let alone the mass that has been left out. Thus the paper broadened to encompass an illustrated report of the Exhibition in general. Including three of the major omitted items.

This paper supplements the brief and necessarily formal Publicity Officer’s Report in the BBS Bulletin 52, 17-18, (1988), which those interested should read.

Why material was cut out

Something in excess of 25,000 words had been originally submitted to me, and this material was collated and rewritten (to about 8,500 words) in eight sections, as a first draft for the proposed eight panels for the Exhibition. This draft was then further savagely cut by Margaret Hartley of Cliffe Castle Museum, Keighley, and myself to only 3,500 words, in order to fit on the space available.

The eight panels are 880 x 1,520 mm (or 3′ x 5′); this size was chosen as being a practical limit for both topics of information, and for travelling and easy assembly. A longer panel would have been outside easy reading height, and wider panels are not easily accommodated in halls suitable for temporary exhibitions. The maximum number of words on any panel is about 750, and the minimum used was 42. Our designers, Hall Redman Associates, quite rightly pointed out that the public will not read a text book on a panel, and that unless an exhibition is attractive and fairly light-weight, then it is unlikely even to get hired.

Audience

The Exhibition was not intended for bryologists; people wander into a museum for many reasons. Many are school children, dragged in unwillingly; others are families looking for a day out (or in, if it is raining). Others may have an Interest in Egyptology, Geology, Ethnology, or any of the other disciplines on display. Few are dedicated naturalists, and hardly any are already “converted” to bryology. Thus the Exhibition had to present mosses and liverworts to catch the attention of someone who is just wandering through a temporary exhibition hall.

Photographic material, etc.

Since preserved bryophytes do not lend themselves to display, the Exhibition used plenty of photographic material to break up the text; there are 94 photographs and other graphic items on the eight panels. Cliffe Castle Museum mounted a supplementary exhibition of over 40 colour prints, mostly 20″ x 16″, but at Manchester this was reduced to a selection of 23. All colour material is Cibachrome, chosen not only because of its quality, but also because of its colour permanence. None-the-less, a large proportion of photographs submitted and available, were (like the text) not used.

Elsewhere is other material, such as books, bags of peat or horticultural moss poles, that may be provided by the borrowing institution. In particular, borrowing institutions are encouraged to construct and maintain a living moss garden; guidelines based on Manchester’s successful garden are now being circulated with the Exhibition.

Mosses pamphlet

The little eight-page A5 duplicated booklet: “Mosses and Liverworts of Town and Garden” (MALOTAG for short) is on sale at the Exhibition, and is intended to be as cheap as possible without making a loss; this works out at about 25p per copy. There are descriptions and line drawings of 49 of the commonest bryophytes. The back page is mostly about the Society, and each copy contains an Application for Membership slip. Several hundred copies were sold at Manchester, but how much seed fell on fertile ground remains to be seen.

Omitted: Schistostega-cave

The Schistostega-cave was intended to be the centrepiece, and I am sure it would still be worth constructing.

Those bryologists who have spent hours bobbing up and down in front of promising rabbit-holes, caves and clefts, and have been rewarded with the emerald glow when the head was held in just the right position, will understand the need to share the experience.

The idea was for a fibre-glass cave, of any suitable size but with a narrow entrance; it could be mounted onto the back of a display panel, and would be painted a dingy earth-colour inside. In the back would be stuck patches of tiny green “balloto”, or little glass beads of the sort that are used on reflective road signs, or the old-fashioned projector screens. Up and behind the viewing public would be positioned a light to illuminate the “protonema”.

But making even a prototype cave would have taken time and money, and the effect might simply not have worked. Moreover, a cave does not lend itself to flat-packing and travelling in the back of lorries. And sadly, because the Schistostega-cave was thought to be a possibility until late in the construction of the Exhibition, there now remains no reference at all to this fascinating moss.

Omitted: Moss bridge Also left out of the Exhibition was the huge Chinese moss bridge, or even any mention of it. Tufa is a soft spongy rock formed when limestone-rich water runs through mossy growth, depositing the limestone around the moss. In time, it hardens to a rock called travertine, which can build up to form dams across rivers, or huge festoons growing from the sides of dripping cliffs. Sometimes these festoons meet across a gorge and form natural bridges. One famous such bridge in China is 167 metres above the river, and was used as a crossing point for transporting goods by mule. Now a railway viaduct has been built over it. (La Touche, 1906).

Omitted: Quotations

Another idea that got lost in the wash, was to scatter about the panels little quotations about mosses and liverworts. The Bryologist used such quotations as fillers for many years, but has now dropped the practice. In fact, there are surprisingly few references to mosses or liverworts in classical literature or poetry, except for passing comments like “mossy woods” or “mossy paths”, which hardly count.

Thus after searching all the dictionaries of quotations and similar works, plus several years of fairly active general looking and asking about, only 56 entries (two of which are suspect) had been accumulated. Indeed, a fair proportion of the quotes are from “Nature Poets” such as John Clare, or “Nature Writers” such as Flora Thompson, and so perhaps these should not really count either. But still, many of them are fascinating, especially to bryologists who have a very special view of these little plants. It is worthwhile for us to see how the objects of our interest are seen by the outside world.

(Postscript: after a display of the Bryological Quotations at the conversazione that evening, many people have sent in more quotations, or corrected some of those on display. Please do send me any more that you know, with comments if you like. I should be particularly pleased to trace the one about “the silvery moss between paving stones”, that Professor Richards thinks may have been from a Victorian novel or such like).

What was not left out

For those who had not yet seen the Exhibition, there followed a slide show of the display as it was displayed at Keighley, illustrating the eight travelling panels plus Keighley’s supplementary exhibition. The eight panels are: Introduction, “Where to Find Mosses” (two panels), “What is a Moss?”, “What’s in a Name?”, “Conservation”, “Bryology”, “What Use are Mosses?”.

Slides were also shown of the Exhibition at Manchester, illustrating how the material can be displayed quite differently according to the facilities and requirements of the borrowing institution.

BBS members are strongly encouraged to visit the Exhibition; its present whereabouts can be determined from Caroline Krzesinska (Exhibitions Officer), Arts and Museum Division (City of Bradford Metropolitan Council), Cartwright Hall, Lister Park, Bradford BD9 4NS; telephone Bradford (0274) 493313. Can I encourage those of you who use your local Museum, to pester it to book the Exhibition?.

Material is available on disk

Those interested in the wealth of information that was left out of the Exhibition, as well as that which was included, can obtain a copy of the text at the 8,500 word stage, plus a few subsequent alterations, on 5¼ floppy disc (WordStar format). Brian O’Shea has a copy, as well as myself. Do send either of us a blank floppy with return Stamped Addressed Envelope.

Acknowledgements I should particularly like to thank all those members of the BBS who contributed the 21,500 words and the hundreds of photographs that did not get used. In fact, many of the contributions overlapped, and thus were used at least in part. All contributions were most gratefully received, and all omissions were due entirely to the need to restrict the number or size of the topics.

Reference

La Touche, T.D. (1906). Note on the Natural Bridge in Gokteik Gorge. Rec. Geol. Surv. India, 33, 49-54.

Mr R.G. Woods (N.C.C., Llandrindod Wells): “Towards conserving bryophytes: a Mid Wales case study.”

Loss of bryophyte rich habitat was probably unparelleled through the 1960’s into the 1970’s. Capital improvement grants paid by the Welsh Office Agriculture department to farmers in less favoured areas resulted in wholesale drainage of wetlands and clearance of native broadleaved woodlands. Grant aid favoured the planting of conifers on blanket bog and the partial drainage of moorland by grips. Pioneer tree clearance schemes on major rivers destroyed riparian epiphytic communities. In the 1980’s the Wildlife and Countryside Act and its amendments changed the climate of opinion. Consultation now takes place before land use changes can occur to most SSSI’s, on felling licence and planting applications to the Forestry Commission and on river drainage schemes. The opportunity to feed advice on conserving bryophytes is now immense. Sadly the data or knowledge is rarely available. As a minimum the officers and members of the Nature Conservancy Council and local Wildlife Trusts need to know what significant bryophytes or bryophyte rich communities occur in their area, where they occur and their management requirements. As a start guidelines might be produced for well circumscribed habitats such as riparian and dead wood species.

After the Annual General Meeting (Minutes in Bulletin 54), the evening continued with the enjoyable innovation of a book sale. Acting with aplomb as auctioneer, Roy Perry was ably supported by David Long in the role of assistant and by Brian O’Shea as accountant. The meeting then continued in a conversazione, during which the demonstrations listed below were displayed. All combined to make this an informative and enjoyable meeting, and our thanks are due to John Edmondson for his efforts in ensuring its success.

Poster session

J.G. Duckett & A. Russell:	Subterranean axes of liverworts: their regeneration and mycorrhizal associations.
S.R. Edwards:	Bryological quotations in literature.
R.A. Finch:	The BBS mapping scheme and atlas.
E.W. Jones:	Bryological books.
H.L.K. Whitehouse:	Stereoscopic photographs of bryophytes seen during the BBS meeting in Scotland, July 1988.
M.J. Wigginton:	Bryophyte flora of Lancashire north of the Ribble.
R.G. Woods:	Consultation as a means of conserving bryophytes.

M.E. Newton

Field meeting

The Sunday Field excursion was held in North Cheshire, and the 30 or so members who participated were able to enjoy a day of sunshine. We gathered at Hatch Mere, then proceeded to Oak Mere, a site for which the Nature Conservancy Council had requested bryological information. On the north side of the site, closely surrounded by woodland, a large artificial former lake (the Serpentine), was found to be colonised by extensive floating Sphagnum carpets, in which S. recurvum was the most abundant species. S. fimbriatum, S. palustre, S. cuspidatum and S. squarrosum were also seen. A few small areas were rich in liverworts, and Gymnocolea inflata, Cladopodiella fluitans, Cephalozia connivens, and C. bicuspidata were recorded. An interesting find here was Cephaloziella elachista* new to Cheshire. On the peaty margins of the main mere, members were interested to see Atrichum crispum in an unusual habitat. We had hoped to search the bryophyte rich margins of the mere, but unfortunately the water was at an exceptionally high level, inundating all but a very small part. The drier woodland surrounding the mere had little of interest, except for Polytrichum longisetum.

After lunch, a few members of a depleted party paid a brief visit to the small but good-quality schwingmoor of Flaxmere. Here the Sphagnum-mire community contained extensive patches of liverworts, and such species as bog rosemary and cranberry. Most of the afternoon was spent searching the varied woodland and bog habitats surrounding Hatch Mere. Sphagnum palustre, S. recurvum, and S. fimbriatum carpeted the woodland floor, and elsewhere more open boggy areas held such species as Calliergon stramineum and Drepanocladus fluitans. Though an apparently ideal habitat for epiphytic species, their absence bore witness to the high level of air pollution in this area. The final addition to the day’s list was Tortula muralis var. aestiva, a good colony of which was found on a brick at the south-west corner of the site.

M.J. Wigginton