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Deteriorated pollen grains have been recorded from Flandrian sediments in three sites near Callander in Perthshire, and diagrams are presented of deteriorated pollen as opposed to the overall pollen totals discussed in the previous paper. The problems of interpreting records of deteriorated pollen are discussed, a format for pollen diagrams conveying detailed information on deteriorated grains is introduced, and the palaeoenvironmental implications of the records are considered. It is shown that major changes in deteriorated pollen totals are common to all three diagrams, with low percentages in the early Flandrian, and pronounced increases in deteriorated totals coincident with the Corylus decline at each site. It is suggested that similar studies at other sites in northern Britain may prove these trends to be consistent features of Flandrian pollen diagrams. [ABSTRACT FROM AUTHOR]

The paper describes how absolute values of pollen deposition may be calculated from the results of volumetric sampling, supplemented by routine meteorological data. Daily mean values of concentration of birch pollen in the air at Lerwick, Shetland in 1970 and 1971 are presented, and these are used to calculate daily and annual depositions. The results are consistent with what is known about the occurrence of tree pollen in fossil and recent deposits in Shetland. [ABSTRACT FROM AUTHOR]

This paper describes palaeoecological studies at Abernethy Forest by means of pollen and macrofossil analysis and radiocarbon dating. It also illustrates the value of stratigraphic macrofossil analysis in conjunction with pollen analysis in increasing the range and detail of palaeoecological reconstructions of past vegetation and environment. A new, large diameter core from Abernethy Forest was radiocarbon dated, and the presence of Late Devensian sediments was confirmed. Clear vegetational changes were recorded. A pioneer grass-sedge vegetation colonized the bare moraine. It developed into a shrub tundra, dominated by Empetrum and Betula nana as a result of the climatic warming during Allerød time. The Younger Dryas climatic deterioration led to the formation of species-rich open vegetation, in which Artemisia was very abundant. At the opening of the Flandrian, at about 9700 B.P., Juniperus and. Betula nana scrub developed, which was later colonized by tree Betula and then Corylus. From about 7225 B.P. Pinus dominated the forest. Throughout, the specific determinations and local derivation of macrofossils enhanced the reconstruction of the upland vegetation. In addition, macrofossils provided the majority of the evidence for the progression of the hydrosere through lake to bog communities. The complementary nature of pollen and macrofossil analyses from the same core is emphasized by a direct comparison of seed and pollen influxes. [ABSTRACT FROM AUTHOR]

The catches of tree pollen at Lerwick in 1970-72 are related to Lamb's catalogue of daily weather types. This is done by examination of weather maps on particular days, and statistically by finding the effectiveness of certain weather types for pollen transport, and by examining the source areas of trajectories. It is found that in April-July, of all days when the surface track is from likely source areas, 50-80% bring measurable amounts of tree pollen to Shetland, depending on the weather type. The results are applied to statistics of the frequencies of the different weather types. It is estimated that the number of days per year of airborne tree pollen at Lerwick is 15±3, and that there has been no secular trend in this figure over the past hundred years. [ABSTRACT FROM AUTHOR]

Sedimentary DNA (sedDNA) has recently emerged as a new proxy for reconstructing past vegetation, but its taphonomy, source area and representation biases need better assessment. We investigated how sedDNA in recent sediments of two small Scottish lakes reflects a major vegetation change, using well-documented 20th Century plantations of exotic conifers as an experimental system., We used next-generation sequencing to barcode sedDNA retrieved from subrecent lake sediments. For comparison, pollen was analysed from the same samples., The sedDNA record contains 73 taxa (mainly genus or species), all but one of which are present in the study area. Pollen and sedDNA shared 35% of taxa, which partly reflects a difference in source area. More aquatic taxa were recorded in sedDNA, whereas taxa assumed to be of regional rather than local origin were recorded only as pollen., The chronology of the sediments and planting records are well aligned, and sedDNA of exotic conifers appears in high quantities with the establishment of plantations around the lakes. SedDNA recorded other changes in local vegetation that accompanied afforestation. There were no signs of DNA leaching in the sediments or DNA originating from pollen. [ABSTRACT FROM AUTHOR]

The article discusses the highlights of a meeting held in Aberdeen, Scotland in late June 2008 to discuss the metabolism and chemical speciation of arsenic (As). Among the topics discussed at the meeting ranged across multiple plant species and scales, from the molecular to the field, and covered a diverse set of processes, from arsenic soil chemistry, plant biological and analytical chemistry, to arsenic contamination of food and approached that could reduce such contamination.

The article discusses the highlights of the 9th European Conference on Fungal Genetics (ECFG), which took place in Edinburgh, Scotland in April 2008. The participants assembled at the University of Edinburgh to learn about the current progress in the field of fungal genetics research. The event featured a considerable number of plant-fungal interaction presentations and posters. Nick Talbot of the University of Exeter discussed the biology of the model pathogen Magnaporthe grisea, which is responsible for rice blast disease.

The article discusses the highlights of a special session on symbioses at the Society for Experimental Biology Annual Main Meeting held in Glasgow, Scotland from March to April 2007. The session was conducted to address some of the issues associated with symbioses. The meeting brought together a wide range of scientists, working on a range of plant, microbial and animal associations.

Summary • The effects of nitrogen (N) deposition on the moss Racomitrium lanuginosum within montane heath in Scotland were investigated over 5 yr. • Permanent field plots were sprayed with KNO[sub 3] or NH[sub 4] Cl solutions, at doses equivalent to 10 and 40 kg N ha[sup -1] yr[sup -1] , in 3–6 applications each summer. • Racomitrium growth and cover were severely reduced by N addition, whilst the proportion of dead shoots greatly increased. N dose decreased inducibility of shoot nitrate reductase activity (NRA), suggesting that N saturation of Racomitrium occurred, and caused an increase in potassium leakage. At high dosage, effects of NH[sub 4] [sup +] were more detrimental than NO[sub 3] [sup -] . • Physiological responses to N indicate that the habitat's critical load (CL) is exceeded by addition of 10 kg N ha[sup -1] yr[sup -1] . The differential toxicity of the two forms of N suggests that predominant ion type in deposition should be taken into consideration when CLs are set. In contrast to tissue N, NRA correlated well with shoot growth, and may thus be a useful biological indicator of moss condition. [ABSTRACT FROM AUTHOR]

• Experiments were conducted to determine the genetic relationship between the alpine fern Athyrium distentifolium and the Scottish endemic taxon A. distentifolium var. flexile. • Segregation of the taxa was studied after growing sporophytes from spore families, and after selfing and crossing gametophytes. The growth of both gametophytes and sporophytes was measured under a range of nutrient regimes. • The distinction between the two taxa is due to variation at a single gene with pleiotropic effects expressed at both the sporophyte and gametophyte stages. A. distentifolium sporophytes (genotypes A&supD;/A&supD; or A&supD;/A&supF; ) are taller, have fewer fronds, and produce fewer spores than A. distentifolium var. flexile sporophytes (genotype A&supF;/A&supF; ). Gametophytes containing the A F allele have a 50% higher growth rate than those with the A&supD; allele on a range of media. • The polymorphism may be maintained by a balance between selection for and against the A&supF; allele at the gametophyte and sporophyte stages of the life cycle, respectively. Implications for the conservation of the A. distentifolium var. flexile taxon are discussed. [ABSTRACT FROM AUTHOR]

Summary •The question ‘are fragmented wild populations of raspberry adaptively differentiated from each other and from cultivated forms of the same species?’ is addressed here. •Plants collected from the coast, where commercial raspberries are grown, northwards by 49 km to an altitude of 600 m in Tayside, Scotland, were cultured in two common environments. Twenty phenotypic traits were recorded over 2 yr, on vegetative primocanes and then the single dominant floricane retained for year 2. A novel approach is presented for selecting traits that best discriminate between individuals using principal coordinate analysis. Phenotypic variation among accessions was then quantified using principal coordinate analysis followed by principal component analysis. •A consistent north–south trend was found. Plants from northern sites were shorter, bushier with less lateral growth and fewer flowers per lateral on the dominant fruiting cane. Plants from southern sites produced few, tall primocanes with greater cane diameters, lateral growth and flowering. The results were consistent across test environments. •The results confirm substantial, adaptive differentiation between populations and suggest a limited effect of cultivation on wild forms. [ABSTRACT FROM AUTHOR]

The ultramafic sites at Meikle Kilrannoch, Scotland, have small sparsely colonized patches with soils which have highly toxic (to many non-indigenous plants) concentration of Mg and Ni. These toxic metals are unlikely to be the main cause of the open vegetation as the indigenous plants are at least partially tolerant of them. The hypothesis that low soil nutrients were a likely cause of the open vegetation was tested by a fertilization experiment in which major nutrients and Ca were added in August 1991 and July 1992 to replicated quadrats which initially had 5.3-6.6% plant cover. There was a large increase in plant cover on major nutrient addition. The increase in rosette size, flowering, seed production, and recruitment if the dominant semelparous Cochlearia pyrenaica DC. ssp. alpina (Bab.) Dalby was studied in detail. The increased growth of Cochlearia (and some other native species at the site) in nutrient addition strengthens the argument that a major nutrient deficiency rather than a metal toxicity limits plants growth at Meikle Kilrannoch and shows that at least some stress tolerators respond with rapid growth and reproduction when nutrient limitation is removed. A small-scale experiment set up in June 1993, in which the major nutrients were added separately, suggested that P and not N, or K was the limiting element. The effects of P seem to be unrelated to any possible reduction in the availability of the toxic ions Mg2+ and Ni2+. [ABSTRACT FROM AUTHOR]

Palaeoecological investigations of two lake sediment sequences art used to reconstruct the vegetation history of the Western Isles. Pollen records begin in the late glacial and show a clear progression from herb-rich grassland with abundant Salix. Rumex and Polypodium to widespread Empetrum nigrum heath. Woodland developed widely in the early Holocene, and regional vegetation patterns emerged. Western Lewis supported extensive areas of birch woodland with Corylus avellana, Salix, Populus and Sorbus aucuparia. Open birch-hazel woodland dominated other lowland regions. Regional variation was accentuated when woodland underwent a sudden decline in western Lewis at about 7900 BP. Trees were replaced by blanket peat and woodland failed to recover on a regional scale after the decline. Woodland continued to diversify in central and eastern regions and, by 6000 BP, Quercus, Ulmus, Pinus sylvestris, Alnus glutinosa and Fraxinus excelsior had become established. Open mixed woodland persisted until the second major decline began between 5200 and 4000 BP. Woodland contracted gradually as blanket peat expanded. The Western Isles were predominantly treeless at 2500 BP. Blanket peat started to form in localized areas on the Western Isles between 9000 and 8000 BP; two main expansion phases are associated with periods of woodland decline. Subfossil wood or macrofossils are reported from a total of 40 sites. Radiocarbon ages are presented for 13 samples of these. [ABSTRACT FROM AUTHOR]

A radiocarbon dated pollen and macrofossil record from Lang Lochs Mire, Shetland, is presented. Late-glacial minerogenic and early Holocene gyttja sediments underlie mid and lute Holocene peat. These indicate that the area was free from ice sometime before 13000 BP and there is evidence for a typical Devensian Late-glacial climatic sequence as recorded elsewhere in Scotland. Until c. 10500 BP an open vegetation with abundant mosses amongst dwarf shrubs and herbs characterized the surrounding area. At c. 10500 BP gyttja deposition starred, aquatic plants became abundant in the loch and Betula woodland developed around the loch. From c. 9700 BP to c. 7700 BP Corylus was also important. During this time Alnus, Quercus and Ulmus pollen values rose but remained compatible with a long distance source for the pollen. At c. 7700 BP gyttja deposition ceased at the sample site and a poor fen developed. Around this, heathland and blanket peat vegetation started to develop from c. 7000 BP. By c. 6000 BP the area was largely treeless and after c. 5000 BP blanket peat spread and eventually dominated all but the steepest slopes. Pollen profile changes after c. 4500 BP can be attributed to either the spread of blanket peat or the effects of Neolithic peoples. The changes coincide with the arrival of Neolithic people elsewhere in Shetland. The first clear indication of Neolithic activity is dated to c. 3000 BP and coincides with increased activity in agriculturally more favourable areas of Shetland. Records of phytogeographically significant species are discussed and the value of combined macrofossil and pollen investigations is illustrated. The combined approach has helped to distinguish site and regional components of the pollen rain, the vegetational development of both the site and the surrounding area and has given a more accurate record of the occurrence of a number of taxa than could be achieved by pollen analysis alone. [ABSTRACT FROM AUTHOR]

Pollen analysis was carried out on sediment sequences from two small basins situated 6 km apart in the hills of west Mainland, Orkney. At both sites, vegetation development from the lateglacial until after the arrival of Neolithic people is recorded. An initial lateglacial heath, interrupted by a herbaceous phase indicating the Younger Dryas, was replaced by tall herb and grassland vegetation. The Saksunarvatn ash layer was recorded, coinciding with the arrival of Corylus avellana in the islands at around 9.2 ka BP. Extensive woodland developed at about 8000 yr BP, predominantly Betula Corylus with Salix, Alnus glutinosa, Quercus and Pinus sylvestris occasionally present. The woodland was locally affected by Mesolithic human activity and finally lost at around 5 ka BP, partly as a consequence of Neolithic human activity. Mire development was actively proceeding in both basins after the woodland decline. The records illustrate the importance of human activity in the development of the treeless, varied landscape seen in Orkney today. [ABSTRACT FROM AUTHOR]

Recent investigations at Camp Fauld in Buchan, Scotland have yielded two peat deposits of pre-Late Devensian age. Percentage pollen diagrams are presented. One peat is radiocarbon-dated to 34--39 ka BP, which prompts correlation with the Hengelo-Denekamp sequence of NW continental Europe. but the pollen evidence, revealing the presence of a birch pine woodland, suggests an earlier stage. The second peat deposit records an open shrubtundra in which Bruckenthalia spiculifolia is present. The peat yielded a radiocarbon date of 40 51 ka BP, but is suspected of having been contaminated by younger carbon. That suspicion and the presence of Bruckenthalia suggest that a correlation, based on the radiocarbon date, with the Glinde interstadial, identified in NW Germany. would be incorrect. Correlation with other Scottish pre-Late Devensian sites has proved to be difficult. [ABSTRACT FROM AUTHOR]

In a 27-month CO2-enrichment experiment, Calluna vulgaris plants were grown on peat obtained from an upland heath in NE Scotland and given a nutrient supply which mimicked that in precipitation in the area. Three CO2 concentrations were used; ambient, +100 ppm and + 200 ppm. Calluna showed a negative growth response to increased CO2 over the first year of treatment and a positive response by the end of the experiment. Final above-ground biomass was greatest in the enriched CO2 treatments, showing an increase of 30% in + 100 ppm CO2. Determination of tissue nutrient concentration, and calculation of total nutrient uptake, demonstrated that nutrient uptake did not increase with increased growth, resulting in significant dilution of elements in leaf tissue. This suggests that, in its typical, nutrient poor habitats, the growth response of Calluna to CO2 will be limited by nutrient deficiency, and will reach a maximum with a relatively small increase in CO2 concentration. Flowering was advanced and extremely prolific in +100 ppm CO2 grown plants, but the ecological significance of this is uncertain. The results highlight the need for long term studies of native species on their natural soils, using lower CO2 concentrations than the usual 'double CO2'. [ABSTRACT FROM AUTHOR]

Two-year-old seedlings of red spruce [Picea rubens Sarg. syn. P. rubra (Du Roi) Link] were grown in open-top chambers supplied with charcoal-filtered air near Edinburgh, Scotland. Between May and November 1988, plants were exposed to mists containing NH4-, SO42- and NO3- ions at concentrations of 1.6 mol m-3 a and H+ at 3.2 mol m-3, in pairwise combination and all together. The mists were applied twice weekly at a rate of 2 mm precipitation equivalent per application. Treatment with H2SO4 severely damaged the planta after 3 wk; the concentration for this treatment was therefore reduced from 1.6 mol m-3 to 0.5 mol m-3 a and new planta were substituted, in June 1988. Frost hardiness was assessed by freeze-testing detached shoots, then measuring rates of electrolyte leakage. No effects of the mist treatments were detected during the early stages of frost hardening, bur on 31 October, shoots that had received sulphate and ammonium ions were less hardy than 'control' shoots treated with deionized water. The temperature which killed 20 % of shoots was 14 °C higher, and the temperature which killed 50% of shoots was 7 °C higher than for 'control' shoots. Acidity per se had no effect on frost hardiness: nitrate ions had no effect and may have mitigated the effects of sulphate when applied together. The results confirm earliar data, and indicate that uptake of NH4+ and SO42- ions can disturb the frosthardening process. There are important implications for pollution control strategies in the northeastern United States, if damaging interactions between frost hardiness of red spruce and pollutant depoaition are linked to ammonium and sulphate rather than nitrate ions. [ABSTRACT FROM AUTHOR]

A Holocene record of pollen, charcoal, magnetic susceptibility and sediment chemistry from South Uist, Western Isles, is described and discussed. The vegetation of eastern South Uist included areas of woodland over as much as half of the available landscape during the early postglacial. This woodland was dominated by Betula and Corylus, but Quercus, Ulmus, Alnus glutinosa and Fraxinus excelsior were also present. The status of Pinus sylvestris is uncertain. Quercus, Ulmus and A. glutinosa are now extinct as native trees in the Western Isles. During the later half of the Holocene (from about 4000 HP), woodland declined, possibly as a result of the use of hill land as grazing. Blanket peat vegetation, which had begun to spread from about 5500 BP, became the dominant feature of the landscape as the woodland areas decreased. The physical and chemical data from Loch Lang sediments Suggest that little erosion of soils took place until about 550 years ago, when there was a marked increase, possibly attributable to increasing grazing pressure. [ABSTRACT FROM AUTHOR]

Pollen percentage and pollen concentration data are described from an infilled basin within a Loch Lomond Stadial end moraine at Gribun on the west coast of the Isle of Mull, Inner Hebrides, Scotland. The pollen profile, which is over 13 m deep, spans most of the Flandrian stage and constitutes one of the most detailed records of post-glacial vegetational change for any area in northern Britain. Nine local pollen assemblage zones and five pollen concentration zones are identified in the pollen diagrams, and these can be correlated with biozones recognized in other profiles on Mull, In general, the data from Gribun confirm the spatial and temporal patterns of Flandrian vegetational developments that have been suggested by these earlier studies. However, the high level of biostratigraphic resolution within the Gribun profile places these palaeobotanical and associated reconstructions on a more secure footing, and it is therefore proposed that Gribun be considered as the type site for the Flandrian stage in this area of western Scotland. [ABSTRACT FROM AUTHOR]

Leaf growth, photosynthesis and soluble carbohydrate content were measured for Lobelia dortmanna L. across one year in a small oligotrophic lochan in the northwest of Scotland at a number of sites, varying in degree of exposure, sediment type, nutrient concentrations and plant form. Leaf production and loss occurred during the entire year, although production and photosynthesis were maximal in the early summer. Soluble carbohydrate was highest in the early spring, and was lowest when leaf production was greatest. Environmental changes (solar irradiance, lochan temperature and water levels) were also related to growth rates, showing a particularly strong correlation between irradiance and the relative leaf growth rate, Little influence of epiphytes or limitation of growth by nutrient or the contribution of inorganic carbon was found. [ABSTRACT FROM AUTHOR]

Monoterpene and isozyme loci, used as markers to study the genetic structure of Scots pine (Pinus sylvestris L.) native to Scotland, showed that the endemic populations are not genetically impoverished, in spite of severe contraction in range and numbers as a result of both natural and anthropogenic causes. On the contrary, variability in the relict populations is almost the highest of any plant species studied, with average heterozygosities of 0.33 for monoterpenes (five loci) and 0.30 for isozymes (16 loci). The overwhelming proportion of this variability (> 950) was within populations, even though significant differences in gene frequencies of many individual loci existed among populations. Multiple-locus comparison of gene frequencies among populations, resolved by canonical variate analysis, showed no coherent geographic pattern of differences from population to population or region to region, with one major exception: certain populations in northwestern Scotland (Wester Ross) were distinct from all others and each other. The pattern of variability of the biochemical markers was consistent with that of metrical and physiological traits reported in the literature. These traits, in turn, show relatively little genetic affinity between contemporary Scottish and continental European populations. The genetic evidence, together with the anomalous distribution of pine pollen in the British lsles during the Holocene, suggests that the Caledonian race of Scots pine originated endemically from more than one refugium after the last glaciation.x [ABSTRACT FROM AUTHOR]

Flandrian percentage pollen diagrams are presented from three sites in Western and northern Mull, Inner Hebrides, Scotland, and these data are augmented by Pollen concentration evidence from one of the sites. In general terms, the pattern of vegetational development is broadly similar to that found in a previous study in the uplands of south-central Mull. However, differences in detail are apparent in the vegetational history of the northern and western parts of the island, particularly in the representation of Empetrum, Juniperus and Betula pollen in the early Flandrian deposits, and in the frequencies of Alnus and Quercus in the mid- and late-Flandrian pollen records. These pollen-stratigraphic contrasts between the three sites, and between these profiles and those from the more sheltered south-central parts of the island can be attributed partly to differences in pollen recruitment processes and partly to variations in degree of exposure to prevailing winds. [ABSTRACT FROM AUTHOR]

Pollen-stratigraphic evidence is presented from three sites in Glen More on the Isle of Mull, Inner Hebrides, Scotland, which spans the time interval from the wastage of the Loch Lomond Advance glaciers to the virtual disappearance of woodland from the island in the Late Flandrian period. Radiocarbon dates suggest that the Isle of Mull was deglaciated by about 10000 B.P., and palynological evidence from the base of the profiles implies time-transgressive deglacial retreat of the ice that occupied Glen More. Wastage of the last glaciers on the island was followed by the expansion of Empetrum heath and juniper scrub, the latter being widespread by about 9600 to 9500 B.P. At that time birch woodland may have been present in the lowlands and in sheltered localities along the coastal fringes, but the spread of Betula into the hills of central Mull appears to have occurred some 200 to 300 years later. Corylus avellana became widely established around 8800 B.P. and was followed by mixed woodland genera including Quercus, Ulmus, Pinus and Alnus. The relatively low representation of arboreal pollen in all three profiles suggests, however, that woodland was never widespread on Mull during the Flandrian due principally, it would seem, to exposure to strong westerly winds. The expansion of grassland and Calluna-dominated heaths during the Late Flandrian reflects a change to wetter climatic conditions, but may also be partly a consequence of anthropogenic activity, particularly in lowland areas. [ABSTRACT FROM AUTHOR]

In a survey of the keel petal colour polymorphism in Lotus corniculatus L. conducted at 61 coastal and inland locations in Scotland, there was a major difference in morph frequency between populations in the west and those in the east and central areas, with the dark keel being at low relative frequency at most western locations. When figures for east and central Scotland were considered, there was a slight but statistically significant increase in the dark keel morph with increasing latitude, a pattern which was not found in Scotland as a whole. [ABSTRACT FROM AUTHOR]

The lithostratigraphy of a section exposed at Sel Ayre on the Walls Peninsula, Shetland Mainland is described. A peat bed 50 cm thick is overlain by 7.3 m of sands, gravels, and boulder clay. Pollen analyses of this peat bed and of peat laminae in the sands reveal three distinctive pollen assemblages. These assemblages are interpreted as reflecting a vegetational development from grass- and fern-dominated communities on fertile brown-earths to dwarf-shrub heaths dominated by ericaceous shrubs including Bruckenthalia spiculifolia. These heaths grew on acid humus-rich podsols and were replaced by open, grass-dominated communities. Numerical comparisons of the Sel Ayre pollen spectra with pollen data from other sites on Shetland using principal components analysis suggest that three interglacial stages are represented on Shetland Mainland - Flandrian, Ipswichian and Hoxnian. On the basis of the composition of the presumed long-distance tree-pollen rain, the Sel Ayre sequence is correlated with the Ipswichian stage. A basic interglacial cycle is proposed for the Shetlands. [ABSTRACT FROM AUTHOR]

The geology, climate and soils of the Caenlochan N.N.R. are briefly described. The flora is discussed and the results of a primary phytosociological survey are described. One hundred and ninety-three relevés were collected from uniform stands of vegetation and analysed using phytosociological techniques. Thirty-four noda are delimited: 9 of them are heath types, 3 are bogs, 9 are grasslands, 4 represent various types of cliff-ledges and 9 are mires, springs, rills and wet flushes. The floristics and ecology of the noda are briefly discussed. The ecological and floristic interrelationships among the noda are discussed. An ordination of the noda using constancy data is used to illustrate these relationships and to identify the principal habitat gradients. Soil base-status and soil moisture are seen to be of primary importance but the secondary importance of land-use history in determining the present vegetation is also emphasized. [ABSTRACT FROM AUTHOR]

The vegetation of the saltmarshes, raised-beaches, inland mires, dwarf-shrub heaths, mountains, and woodlands of the Isle of Arran are described using conventional European phytosociological methods. The floristic affinities of these communities with previously delimited units elsewhere in Britain and in western Europe are described, and the problems of assigning many of the Arran communities into the existing central European phytosociological hierarchy are discussed. [ABSTRACT FROM AUTHOR]

A cytological survey of two populations of Betula in Northeast Scotland revealed the existence of 2n = 28, 2n = 56, 2n = 42 cytotypes. In addition, putative mixoploids with mean somatic counts between 2n = 45 and 2n = 52 were found. The 2n = 42 and mixoploid trees are similar in morphology to the 2n = 56 trees and cannot be distinguished in the field. Seed from uncontrolled pollination of the 2n = 42 cytotypes produced seedlings with somatic counts ranging from 2n = 35 to 2n = 56 with 50% of seedlings being 2n = 42. [ABSTRACT FROM AUTHOR]

Recent developments in the classification of the earliest vascular plants are discussed. The fertile parts of Hicklingia edwardii, a remarkably well preserved plant from the Middle Old Red Sandstone of Scotland, are described. It is concluded that this plant had lateral not terminal sporangia and may be assigned provisionally to the Zosterophyllophytina until more is known about its anatomy. [ABSTRACT FROM AUTHOR]

Two pollen diagrams are presented, one from Murraster, Shetland Mainland, and one from Hoydalar, Streymoy, Faroe Islands. Both localities are former lakes, now filled up, and in both places the sedimentation started about 10,000 years ago. In the Faroese diagram herbs are dominant throughout, while it can be seen that Juniperus and Salix have been of considerable significance and Betula nana has had a wide distribution in early Flandrian time. In the Shetland diagram large-leaved Betula and Corylus are also present, even though herbs were also dominant. [ABSTRACT FROM AUTHOR]

North Hoy is an area containing a remarkable diversity of vegetation in a small area. A phytosociological account of the hill vegetation of North Hoy is presented, making use of an ordination method to clarify the inter-relationships of the moorland vegetation types, as well as traditional methods. It has proved very interesting to compare the vegetation with the account of Scottish Highland vegetation by McVean and Ratcliffe (1962). Birks' (1973) account of the vegetation of Skye has also been drawn on, particularly as a source for a system of classes, orders and alliances applicable to Scottish vegetation. The environmental background (climate, topography, geology, patterned ground phenomena, animal populations and past and present land-use) is summarized. Several important general features of the vegetation of North Hoy deserve emphasis, especially from a conservation point of view. (1) Many good examples of noda characteristic of strongly basic soils, especially mires and grasslands, are found. Some of these have a rather restricted distribution in Scotland. (2) Small areas of woodland, including one very species-rich wood, are found in sheltered ravines. These are well-developed and regenerating, and represent the northernmost occurrence of woodland in Britain. (3) Many species and many types of vegetation occur at unusually low altitudes (as is also observed in northernmost Sutherland, Caithness and Shetland). Particularly interesting are certain montane dwarf heaths, which are associated with well-developed patterned ground features. (4) The area contains both occurrences of 'Atlantic' bryophytes and well-developed stands of lichen heath and lichen-rich bog, which have a strongly 'continental' distribution in Scotland. This apparent paradox is discussed but not resolved. (5) The low level of sheep-grazing and absence of burning in recent years have led to some unusual vegetation features. Phytosociological tables are presented in an appendix. [ABSTRACT FROM AUTHOR]

All the grasses and nearly all the dicotyledonous plants growing on three coal tips in Scotland were infected by vesicular-arbuscular mycorrhizal fungi. Infection levels ranged from 20 to 90%. Three main types of fungal endophytes were identified, two being Endogone spp. and one with very narrow hyphae. Mixed infections were present in some plants and there was some evidence that the endophytes occurred in different areas of the tips. The ecological importance of the mycorrhizas in these habitats is discussed. [ABSTRACT FROM AUTHOR]

Tree pollen was found in the air at Lerwick, Shetland in May and June 1970 and April and May 1971. The predominant species were birch and pine, and peak concentrations (daily mean) of 20 and 30 grains m-3 respectively, were recorded. Trajectories on surface meteorological charts give good agreement of the catch with likely source areas in Scandinavia and Britain. Possible applications and extensions of the work are mentioned briefly. [ABSTRACT FROM AUTHOR]

An isolate of the purple-brown spored agaric Psilocybe merdaria (Fr.) Ricken, which had been collected on Mull, Scotland, was found to be unstable in its morphological characters when in pure culture. Apart from normal fruit-bodies a series of forms developed, ranging from laterally stipitate to gasteromycetoid ones. The morphological characters of the two extreme forms, before and after several subcultures were made, are described. How these abnormal fruit-bodies might amplify past and present theories on the origin of the Gasteromycetes is considered. The shape of the basidium in this one isolate was also found to be plastic and several deviations from the typical basidium are described. It is suggested that the origin of at least some types of pleurocystidia should be sought in modifications of the basidium. The use of the basidium as a major character in the classification of the Basidiomycetes is not discredited, but a closer relationship than previously expressed between the different groups of the higher fungi is argued. It is suggested that useful information might be obtained from the further study of teratological forms similar to those of P. merdaria whenever they are found in other higher fungi. In the field aberrant forms are not as rare as might be at first supposed. [ABSTRACT FROM AUTHOR]

The article presents a study of stratigraphy, pollen and other organic material of deposits at Corstorphine, Edinburgh, Scotland. Lacustrine deposits at Corstorphine are situated in western Edinburgh, lyning within a broad west to east depression several mile in length. The lacustrine deposits consist of two distinct series. Lower beds are marls, clays and silts of Late-Weichselian age and upper are thin muds and silty layers representing deposits of the Flandrian stage of the loch.Small, isolated patches of the younger organic material occur in shalloow depressions in the surface of teh sand and gravel horizon.

A virus which is pathogenic to certain blue-green algae belonging to the genera Plectonema, Phormidium and Lyngbya has been isolated from a variety of freshwater habitats in Scotland and has been detected over a 12-month period in one of these habitats. The virus (D-1) is a cyanophage, has an isohedral head and a short tail and is morphologically and serologically related to the LPP-1 virus isolated from the United States and the G111 virus isolated from Israel by other workers. The partially purified virus has an absorption spectrum characteristic of a nucleoprotein with a maximum at 260 nm and a minimum at 243 nm. D-1 is temperature sensitive being inactivated on heating at 60° C for 6 minutes. Its multiplication rate is fast, increasing from an initial titre of 10[SUP3] to 10[SUP12]PFU/ml within 40 hours. The lysis of the host cell results in a rapid loss of the phycobilin and chlorophyll pigments. [ABSTRACT FROM AUTHOR]