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This account provides information on all aspects of the biology of Neottia nidus‐avis (L.) Rich. (Bird's‐nest Orchid) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of Britain and Ireland: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, reproductive characteristics, herbivory, history and conservation.Neottia nidus‐avis is a native mycoheterotrophic orchid; it is found most frequently in the deep humus of densely shaded beech woodlands, on limestone or chalky soils in the British Isles. The species extends throughout temperate Eurasia.Neottia nidus‐avis is a perennial, mostly monocarpic herb with mixed mode of reproduction and many adaptations to autogamy. The perennating organ is a short rhizome; vegetative reproduction by rhizome branching or root‐sprouting is rather infrequent. Because of its achlorophyllous nature, N. nidus‐avis is entirely dependent on its mycorrhizal basidiomycetes from the family Sebacinaceae for nutrition.Plastid genome of N. nidus‐avis has been reduced as a result of the relaxation of functional constraints on photosynthesis as in other mycoheterotrophic plants. Despite this, the plant has retained all enzymes to produce chlorophyll as well as some photoprotective metabolites, such as zeaxanthin and tocopherol, whose function in the mycoheterotrophic plant remains unresolved.The species flowers from May to June, depending on latitude and altitude. The flowers emit a sweet scent and produce little nectar. They may be pollinated by flies, crawling thrips and ants but self‐pollination is presumed to be the main mode of reproduction. Between 75% and 97% of open flowers set fruits.Neottia nidus‐avis is classified as Vulnerable in Great Britain. The species is scattered throughout much of the British Isles, but it is very scarce except in southern England, where it is locally abundant. The main threats are deforestation, changes in woodland management and coniferization. [ABSTRACT FROM AUTHOR]

A large-scale database concerning benthic copepods from the Arctic, Baltic Sea, North Sea, British Isles, Adriatic Sea and Crete was compiled to assess species richness, biodiversity, communities, ecological range size and biogeographical patterns. The Adriatic showed the highest evenness and the most species-rich communities. Assemblages from the North Sea, British Isles, Baltic and Crete had a lower evenness. The British Isles were characterised by impoverished communities. The ecological specificity of copepod species showed two diverging trends: higher specificity of species in more diverse assemblages was observed in the Adriatic, North Sea and Baltic. A uniformly high species specificity disregarding sample diversity was found on Crete and in the British Isles. Benthic copepod communities showed distinct patterns that clearly fit the predefined geographical regions. Communities were distinguishable and β-diversity was found to be high around Europe, indicating a high species turnover on the scale of this investigation. The British Isles and the North Sea were found to be faunistic links to the Baltic and the Arctic. [ABSTRACT FROM AUTHOR]

Analysis of size of offspring reared through three laboratory generations from populations of the field grasshopper Chorthippus brunneus from 27 sites around the British Isles showed that offspring were larger towards the cooler-wetter conditions in the western and northern limits of the range. This variation had a significant genetic component. There was a trade-off between clutch size and offspring size between and within populations. Under favourable thermal and feeding conditions maternal fitness was optimal when individuals produced the largest clutches of the smallest eggs, but under poor conditions maternal fitness was optimal when individuals produced small clutches of very large offspring. Calculation of geometric mean fitness over time indicated that having larger offspring near to the edge of the range could be advantageous as a conservative risk-spreading strategy. As well as geographic variation in egg size, significant environment–genotype interactions in egg size in relation to temperature were observed. [ABSTRACT FROM AUTHOR]

Focuses on the biological flora of the British Isles. Identification of common Cynoglossum species; Composition and habitat of individual plants; Height of flowering stalk.

Characterizes the biological flora of the British Isles. Geographical and altitudinal distribution of plants in the area; Climatic and topographical limitations.

The article focuses on Vulpria fasciculata in the British Isles. V. fasciculata is a small annual grass, solitary or loosely tufted, 2-40(-60) cm high. Leaves are dark green, sometimes purplish, especially in late winter, and generally inrolled and sickle-shaped in young and small plants. Sheaths are usually overlapping, somewhat inflated, glabrous and rounded on the abaxial surface. Considerable phenotypic plasticity is shown, particularly in height, the number of tillers and the number of spikelets per inflorescence. Populations grown in an unheated glasshouse from seed from North Wales were found to show differences in germination time, flowering time, spikelet number, inflorescence height and leaf number.

The article focuses on the biological flora of the British Isles. Subgenus Ficaria (Huds.) L. Benson is perennial terrestrial herb with white adventitious roots. distribution. Diploid populations of Ranunculus ficaria are restricted to western Europe. The subspecies is widely distributed throughout the British Isles. R. ficaria tolerates a wide range of soil types in terms both of chemical and physical properties. Ranunculus ficaria is most commonly found in mixed deciduous woodland in which oak is dominant or co-dominant with other species.

A biometric study of herbarium, wild and cultivated specimens of Caltha palustris L. s.l. in th British Isles indicates that most of the variation in the wild is environmentally determined. Further, there is no correlation of morphology with cytological differentiation. All taxa previously described within C. palustris L. are consequently regarded as untenable, with the exception of plants which differ by the single character of rooting at the nodes, and which show partial geographical differentiation. They are reduced to varietal status. [ABSTRACT FROM AUTHOR]