Plants of Boea hygroscopica were grown in a controlled environment. Control leaves were detached from plants grown in well-watered conditions and then subjected for 144 h to rapid or slow dehydration. Dehydrated leaves were then rehydrated for 36 h in distilled water. Rapid-dried leaves were not able to revive, whereas slow-dried leaves recovered their normal metabolic status. Results showed a different superoxide radical production in the dehydrated leaves accompanied by an altered lipid composition. Rehydrated leaves recovered the original lipid composition of control leaves. Spin-labelled thylakoid proteins of dehydrated leaves showed lower -SH group levels and increased spin motion.

The major antioxidants present in the essential (volatile) oils of oregano (Origanum vulgare, L.), summer savory (Satureja hortensis, L.) and thyme (Thymus vulgaris, L.) have been identified as carvacrol and thymol which have both been demonstrated to possess fungicidal and bactericidal properties. EPR spectra produced upon oxidation are inconsistent with the expected phenoxy free radicals (RO), but resemble those of galvinoxyl and anthronyl radicals. The EPR spectrum, in the case of carvacrol, is a pair of quintets with isotropic splittings, 0.325 and 0.080 millitesla (mT). ENDOR and TRIPLE resonance experiments have been performed and are indicative of the paramagnetic species being a substituted anthronyl. Further studies are being conducted to characterise these species and to investigate their potential roles during oxidative stress.

In Dutch coastal dunes, geomorphological and geohydrological processes have been adversely affected by intensive utilisation of the dunes. In the past, wide-scale stabilisation, notably for reasons of coastal defence, stopped nearly all aeolian activity. Rejuvenation did not take place and succession to mature-type ecosystems increased. Artificial infiltration with eutrophic river water and extraction of groundwater for drinking water catchment modified the geohydrology of the wet-dune environment.

Today, actions are being taken to restore geomorphological and geohydrological processes. Managing authorities join forces with universities and policy makers to strike the right balance between conflicting interests. Applied research helps to develop management strategies.

Two types of research are discussed: (a) geomorphological work on the development of blow-outs; (b) geohydrological work on the development of dune slacks. Questions considered are: do blow-outs grow to an unlimited extent or do they have optimum size and shape corresponding to aerodynamic conditions? Are there natural stabilisation mechanisms for blow-outs? What is the ecological impact of drinking water catchment? Which aspects should be considered to restore the dune slack environment in catchment areas?

Our findings are that blow-outs in The Netherlands have an optimum length:width ratio of about 2 with a blow-out length varying between 20 and 30 m. After 10–15 years without artificial stabilisation measures, the areas studied present an average of about one blow-out per hectare. Natural stabilisation mechanisms include algae which colonise deflation sites inside the blow-out and low secondary dunes which develop at the immediate leeward side of the blow-out. Blow-outs situated at or near downhill slopes of 6–12° may easily extend into larger deflation surfaces. Water erosion, probably caused by the water-repellency of humus-rich top soil, often precedes wind erosion on south- and south-east oriented slopes.

Drinking water production caused dessiccation of dune slacks and the disappearance of associated vegetation. In areas where infiltration with river water from outside the dunes is also applied, inudation and eutrophication drastically changed the dune environment. Nitrophilous plants appeared, especialy along banks of infiltration ponds, but also in seepage ponds. The plant cover depends on nutrient concentration of the (infiltrated) groundwater but especially on the flux of the groundwater. A high rate of flux leads to high nutrient loads, encouraging the growth and eventually dominance of nitrophilous plants. Restoration of dune slacks depends on the quality and the flux of the groundwater, on the streamlines of the groundwater flow in the dune body in relation to the orientation of the seepage ponds, on the presence of peaty or clayey adsorptive layers in the subsoil and possibly also on the presence of a rainwater lens occurring on top of the infiltration water.

Macrobenthic bioturbation and microbial activity can have major ecological effects on present day marine sediments some of which are also seen in the fossil record. The coastal and estuarine sediments in the Clyde Estuary area are described. They contain very high densities of benthic macroorganisms and microorganisms. These organisms have dramatic effects on the physical and chemical properties of sediments, and field and laboratory studies have shown that many geotechnical and geochemical properties of sediments are dictated by them. The effects can be on a microscale of a few millimetres horizontally or vertically (micro-spatial variation), or can have large scale consequences over hundreds of metres (macro-spatial variation).

Sediment stability (shear strength and critical erosion velocity), permeability and particle sedimentation are all altered by macro-invertebrate bioturbation or microbial activity, and many chemical properties such as Eh and pH may be influenced in a similar manner.

Biological activity may therefore play a major role in modifying sediment geotechnics and early sediment diagenesis. It also has direct relevance to the siting of man-made structures on the sea-bed and to sediment stability and transport in estuaries. In situ seeding experiments may lead to biological control and manipulation of these most important field phenomena.

The Outer Hebrides comprise approximately 1·3% of the land area but 15·8% of the area of standing waters of Great Britain. Streams there are generally small and only three are as large as fifth order. The majority of the lochs occur below 200 m altitude and are less than 25 ha in area. A total of 1375 stream systems enter the sea, and drain the land mass through 9240 stream segments. There are just over 6000 lochs, of which less than half are connected to these networks. Most of the water systems are on geologically base-poor rock or soil, and less than 3%, situated on machair, are base-rich and eutrophic. The islands, due to their situation, receive precipitation in the form of very dilute sea water (with some non-marine sulphate probably derived from fossil fuel combustion) and this leads to unusual concentrations of chloride in the inland waters. Metamorphic rocks are resistant to weathering, so there is usually little variation in the composition of fresh waters except in the machair areas, where calcareous sands affect calcium concentrations and alkalinities.

The flora and fauna reflect the aqueous conditions and there are some unique successions of species from high to low salinities even in the same water body. The lochs provide a wide range of habitats for aquatic vegetation, ranging from the rich machair lochs to the oligotrophic peaty lochs (which show marked similarities with their counterparts on the mainland). Three broad categories can be delineated on the basis of their water quality and vegetation: brackish lochs with varying degrees of marine influence, calcareous machair lochs which may also be affected by sea connections, and the peaty lochans of low alkalinity. A few brackish water animals are sufficiently euryhaline to exist in the machair lochs, which are otherwise dominated by freshwater species. The occurrence of chloride in inland waters enables some crustaceans, e.g. Neomysis integer, Gammarus duebeni and Diaptomus wierzejskii to extend into what are poor freshwater habitats. The main constituents of the freshwater fauna are molluscs and arthropods, and a few species of euryhaline fishes, i.e. salmon, sea and brown trout, three-spined and ten-spined sticklebacks and eels. There are some populations of non-migratory charr. No amphibians are present.

Various species of the lamellibranch Gryphœa have received much attention from palæontologists in the past twenty years, partly because careful collecting appears to have produced continuous series of forms (lineages) and partly owing to the problems which are raised by their progressive development from more normal oysters.

The alkaloids of Ragwort (Senecio jacobæa Linn.) are known to be hepatotoxic to farm animals and man. Survivors invariably show permanent impairment of the liver, manifested by cirrhosis and its sequelæ. Senecio infusions may be consumed in small amounts in Britain as a herbal remedy, and in South Africa the Bantu frequently incorporate them in native medicines. It has been shown that these tribes have a high incidence of cirrhosis and primary liver cancer, and there is good evidence that their deficient diet may play an important part in sensitizing the liver to toxins. In the present study, the ragwort alkaloid seneciphylline has been administered by injection to fowls maintained on both adequate and deficient diets, and further fowls received the dried plant in their food. A significant proportion of these birds subsequently developed primary liver tumours. Although there was a higher mortality rate in both treated and controls fed the deficient diet, there was no evidence of a greater tendency to develop liver tumours compared with the birds on the balanced diet.

It is also suggested that the condition known as “cavernous angioma” of the liver of cattle and sheep in Britain may be due to ingestion of ragwort in sub-lethal amounts.

In the Inner Hebrides Mesozoic sediments rest unconformably on much older, harder and more deformed rocks: they are overlain by Tertiary lavas and cut by sub-volcanic intrusions. The Triassic rocks are unfossiliferous conglomerates and sandstones, deposited on alluvial fans and river flood plains in a semiarid climate. Active faults controlled sedimentation. In the early Jurassic the sea transgressed across the region; a basin of net sediment accumulation lay between uplifted regions now represented by the Highlands and the Outer Hebrides. The lower and lower-middle Jurassic is composed of marine shalesandstone alternations comparable to those providing the sources and reservoirs for North Sea oil. Ammonites provide good correlation with the European succession. In the Great Estuarine Group, environments ranged from lagoonal to deltaic to dolomitic mud-flat. Molluscan assemblages can be compared to modern brackish-water faunas. In the upper Jurassic there is a return to marine shales and minor sandstones; ammonites help correlation between Europe and the Boreal province. The lower Cretaceous is absent; thin upper Cretaceous rests disconformably on older rocks. The rocks are not metamorphosed except slightly near the Tertiary plutonic centres. Their softness makes them susceptible to erosion, and, especially where shales are overlain by basalts, extensive landslips occur.

The larger fungi associated with British willows are separated into several groups depending on their resource relationship, trophic state and whether associated with dwarf or arborescent species. Over 150 potentially mycorrhizal taxa have been recorded with willows in Britain, with nearly one-third restricted to arborescent communities. The fungi associated with creeping willow form a distinct category probably reflecting former ecological conditions. While some of the necrotrophic and mycorrhizal fungi are restricted to willows, the saprotrophs are often more widespread and exhibit less specificity.

The plankton in Loch Craiglin was sampled at Station I, the deepest part of the loch. Samples were taken at intervals of two or three weeks, and since, as is mentioned below, the sampling of zooplankton was unreliable for part of 1942, the results for that year are referred to only briefly and the more complete results of 1943 given in detail.

The present paper is the third of a series of studies on the coccidia of Indian birds, and contains the description of six new species of these parasites, four of which belong to the genus Isospora, and one each to the genera Dorisiella and Eimeria, All the parasites described here belong to the Order Coccidiida, Family Eimeriidae. New avian hosts for some already known species are recorded here. The life-history of Eimeria barbeta Kar (1944) is described in detail. We also add here an amended description of Isospora ginginiana Chakravarty and Kar (1944 b), and a new variety of the latter.

The majority of the birds were purchased from local dealers, while some were collected from Gaya, Bihar. Of twenty-eight different species of birds examined, eighteen were parasitized. The table at the end of this paper will indicate the number of birds parasitized (21) out of the total number examined (48), together with the locality of the hosts. Some of the birds were also infected with other protozoan parasites (haemosporidians and flagellates), descriptions of which are being published elsewhere.

The methods adopted here are the same as previously employed by the authors (Chakravarty and Kar, 1944 a and b).

Two species of birds, viz. the large Indian paroquet Psittacula eupatria nipalensis (Hodgs.) and the red-whiskered or Chinese bulbul Elathea jocosa emeria (Linn.), harboured a new Isospora, which does not resemble any known species of this genus. It is therefore proposed to call it Isospora psittaculae n. sp. after one of its hosts.

The surveys of temperature and salinity that have led to the concept that the Gulf Stream splits into branches are reviewed, beginning with the survey made by Helland-Hansen on board the Michael Sars in 1910. The system of currents, or branches, between the Newfoundland Banks and the Mid- Atlantic deduced by the different investigations from charts of temperature, or by dynamic computation, are not all compatible. There is good evidence that part of the Gulf Stream turns south-east after passing the Newfoundland Banks and part turns north to become the North Atlantic Current. Both these currents are boundaries between water masses in the upper layer of the ocean. The evidence for permanent currents other than these two is conflicting.

Sediments from the River Tay contained higher concentrations of ammonia than nitrate throughout an 18 month sampling cycle. Sediments from Kingoodie Bay and from the North Sea off the Tay Estuary produced nitrite and ammonia when incubated in the presence of nitrate.

The nitrate-reducing bacteria present in Kingoodie Bay sediments were Aeromonasj Vibrio organisms with smaller numbers of enterobacteria and pseudomonads and even smaller numbers of acinetobacters. Continuous culture enrichments of sediments showed that in media containing no added NaCl, acinetobacters predominated anaerobically in the presence of nitrate and acetate while enterobacteria predominated in the presence of nitrate and glycerol. With 0.2M NaCl added to media enterobacteria were predominant, irrespective of carbon source, while with 0.4M NaCl addition pseudomonads predominated in acetate and enterobacteria in glycerol media.

These results indicate that, at the salinities observed in the Tay Estuary at Kingoodie Bay, fermentative bacteria are most likely to be active in nitrate reduction.

The contrasting geological and topographical features of different regions of Loch Lomond and its watershed are reflected in the nature of the bottom deposits of the lake. This paper presents a survey of the lake bed with the object of determining the extent of its regional variety, and confirms the validity of regarding the lake as divisible into two primary regions. The two primary regions, “upper loch” and “lower loch”, are clearly distinct, but the case for the separation of part of the lower loch as a third, intermediate, region cannot be dismissed without further investigation. From a comparison of the bottom deposits, an attempt is made to show the advance in trophic state made by the lower loch over that of the upper.

Eighty-four potentially mycorrhizal macrofungi have been recorded with Sitka spruce in Scotland. They derive primarily from the native flora of birch and pine and many are fungi with a wide host range. Specific mycorrhizal associates do not occur. In its native range hypogeous fungi are important but these are largely absent from Scotland. The regularly encountered mycorrhizal flora is less abundant and less diverse than that of Norway spruce or European larch and reflects the importation of Sitka spruce by seed and the ecological conditions to which it gives rise. The saprotrophic macrofungi are species which are widespread and common in a range of vegetation types.

Brady's (1880) Challenger report mentioned only three species of planktonic ostracods, all halocyprids. At that time only 10 halocyprid species were known and only 14 papers had been written on the group. The major burst of interest came in the twenty years 1890–1909, when first Claus and then G. W. Müller published series of papers describing the majority of the present species. Table 1 shows the wax and wane in the numbers of papers published and the species described by decades since 1849 when Dana described the first species. The table clearly shows the recent upsurge of interest in the group. Many of the papers include only passing mention of planktonic ostracods, and so this review attempts to assemble all these scattered references so that the ecological importance of the group can be appreciated and further research requirements become clearer

Some main uses of the versatile genus Salix are described. The basket willow industry, once nationwide but now concentrated in Somerset, is covered in some detail, noting the site requirements and attributes of the three main basket willow species, Salix triandra L., S. viminalis L. and S. purpurea L. The management of the crops and methods of processing to give the ‘white’ or ‘buff’ coloured rods preferred by basket makers are described, as are the ability and versatility of basketry to produce containers uniquely suited to meet specific needs.

Other uses of the shrub willows (sub-genus Vetrix) are outlined, including the stabilisation of slopes and other aspects of bioengineering, amelioration of difficult environments and large-scale amenity urban and motorway plantings.

Attention is drawn to opportunities to develop the tree willows (sub-genus Salix) to meet projected timber shortages, to the use of willows for windbreaks and shelter, and to the culture and use of that very British tree – the Cricket Bat Willow (S. alba var. caerulea (Sm.) Sm.).

Coastal foredune management begins with an understanding of and appreciation for the dynamics of dune creation, development and decay. Sediment exchange between the dune and beach components of the total dune–beach profile is a necessary element in foredune creation and development. Foredune development is enhanced by a slightly negative total dune–beach budget. Foredune crestlines display alongshore periodicities in displacement that are related to beach processes. Effective management is based on the dimensions of the alongshore foredune variations and the retention of sediment in the migrating foredune system.

Oestrogens may be involved in breast cancer development by at least three mechanisms, all of which involve stimulation of growth. Firstly, they may stimulate proliferation of the normal gland and possibly expand the pool of cells susceptible to carcinogens; secondly, they may expand the population of cells initiated by carcinogens by a promoting action to produce clinically detectable tumours; and thirdly, they may stimulate the growth and progression of infiltrating tumours. All of these effects are probably produced by interactions with the oestrogen receptor. There is suggestive evidence from immunocytochemical studies that promotion to the phase of carcinoma in situ in volves expansion of a receptor-positive clone of cells. After progression, there is a gradual loss of endocrine responsiveness either because of loss of the receptor protein or of receptor function. The high proportion of receptor-positive cells in early malignant lesions holds great hope for preventive strategies using anti-oestrogens for suppression of ovarian oestrogen production.

Soil Collembola may be partially responsible for observed reductions in effectiveness of vesicular-arbuscular mycorrhizal (VAM) associations in the field, compared with sterile soil experiments. Feeding damage to hyphae in soil is envisaged as a mechanism by which translocation of phosphorous from beyond root depletion zones to the plants is reduced. Previous work has demonstrated such effects in pots and in a cultivated field plot, and direct observation of feeding has been made. This paper briefly reviews this evidence and presents an experiment in which insecticide reduced the density of Collembola in a seminatural grassland soil, and increased phosphorus inflow into roots of Holcus lanatus. In addition, survey data are reported which show that hyphal grazing is ecologically feasible, as Collembola and infected roots are spatially associated with one another in the soil profile. It is suggested that hyphal grazing by these arthropods has important consequences for VAM function in natural vegetation systems.