Curl-tip disease of bracken (Pteridium aquilinum) is recorded from many sites in Great Britain. Evidence is presented which corroborates the findings of earlier workers that more than one organism is associated with the disease. Three fungi (Phoma aquilina, Ascochyta pteridis and Septoria sp.) are commonly isolated, even from the first visible necroses, suggesting that synergism may operate in pathogenesis. However, Phoma aquilina Sacc. and Penz. is more pathogenic than the others when used independently in inoculations via wounds into bracken raised in growth cabinets or the greenhouse. Field trials of a formulation of spores of P. aquilina, suspended in a dilute solution of the herbicide ioxynil with broth and glycerol, are reported. The potential of such a mycoherbicide for bracken control is considered.

The large hydro-electric schemes developed by the early 1960s now (1984/85) supply 12% of Scottish electricity demand. The pumped storage schemes contribute to the balance of production and demand but are not nett producers of electric power. Schemes remaining for development are numerous but small, in the range below 10 MW. Private development for local use is the best economic prospect for schemes below 500 kW. A rolling five-year programme of 10–15 MW per annum is suggested for the development of remaining resources. In Scottish conditions, peat does not appear to be a viable alternative to diesel power. Wave power is practicable, but probable costs are too high to justify investment at present. Wind power is promising, especially for island sites, but not as a complete replacement for diesel. Developments since 1980 include a successful small machine on Fair Isle and machines at 250 and 300 kW on Orkney where a 3 MW generator is being erected. A 750 kW machine has been ordered for Shetland.

A lack of modern river-borne sediment and a steady supply of marine materials have led to the hypothesis that the upper Tay estuary is undergoing an erosive phase counterbalanced by a headward moving sheet of largely marine-derived sand presently occupying the upper-middle estuary. This primal division (based on sediment budget criteria) is also reflected in the bathymetry, distribution of sediment types, and sedimentary structures. The situation of two contrasting ‘phase zones’ juxtaposed within a relatively small area is ideal for an empirical and indirect analysis of the response of a wide variety of sediment types to the gross physical processes acting on them. The analysis takes the form of standard grain-size characterisations using conventional sedimentary statistics, supplemented by adaptations of C-M and QDa-Md diagrams transformed for display on distribution maps.

The expression of heritable variation in mammals is usually studied among the attributes of the adult; for example, in the body weight, milk yield, or colour of the pelt. A relatively new subject of study is that of heritable variation in the characteristics of gametes. It is of particular interest, because such variation in gametes may affect their fertility, which in turn might have repercussions on both fundamental and applied genetics. Current research is directed mainly to surveying the ways in which spermatozoa are subject to genetic influences. In the present work, heritable variations in the spermatozoa of mice are demonstrated, in the form of differences between inbred strains. The results are in virtually complete agreement with those of a previous study. It has also been found that variation in first generation crosses made from the pure strains can be largely accounted for by a blending inheritance of the characteristics of the parental types, together with an effect of heterosis. This appears to be the first demonstration in gametes of the phenomenon of heterosis, which is nearly but not quite the same as “hybrid vigour”.

There are two commonly met with types of defective eggs laid by the domestic hen that result in considerable financial loss to the poultry farmer, and are frequent enough in their occurrence to affect perceptibly the potential food supply derived from the poultry industry.

The first of these results from the inclusion of blood or meat spots in eggs, and the second is the production of eggs so small as to make the majority of them unsaleable—the so-called “Miniature” eggs.

The presence of blood on the yolk of an egg was recorded by Aristotle as early as 300 B.C., and he attributed it to premature ovulation. Later, about A.D. 1600, Fabricius (Adelmann, 1942), during a demonstration of “sanguineous” eggs to his anatomy class, described a livercoloured body included in an egg. The occurrence of blood spots in eggs led both these authors to propound the theory that the yolk was directly formed from blood.

The estuary and Firth of Forth support an outstanding number and variety of wildfowl and waders at migration seasons and in midwinter. Although populations of wildfowl and waders fell from 25–35,000 and 50–65,000 respectively in the 1970s, to 10–15,000 and 30–40,000 by the mid-1980s, the Forth remains one of few British estuaries to support more than fifteen waterfowl species of national importance for conservation. The ecology and decline of diving ducks off Edinburgh and population studies of shelduck have been given particular attention by researchers. Among waders, distributions, movements and feeding have been studied in detail. The causes of the recent declines amongst waders, notably for knot (Calidris canutus) and dunlin (Calidris alpina) on the estuarine Forth, remain uncertain, but are likely to include natural factors as well as those linked to man's activities.

Red deer are now being farmed for meal production on an intensive scale. They are manageable, adaptable and healthy animals, and. with care and good nutrition, they become far more productive than wild deer.

Their digestive efficiency resembles that of sheep. Productive activities caking and lactation, fattening and antler growth occur in summer when food is plentiful and depend on endocrine and metabolic cycles entrained by day length. Dietary energy needs of deer are similar to those of cattle but higher than those of sheep: however, because young deer store little fat, they produce lean meat as efficiently as sheep.

Deer produce rich milk: the growth of sucking calves reflects the supply of nutrients available to their dams. In winter, calves benefit from shelter: nonetheless, their growth and appetite decline, even when day length is experimentally lengthened. While good nutrition improves winter growth, this is costly: furthermore, improved winter growth is followed by somewhat poorer growth during the succeeding summer. Slaughter of calves at 6 months of age rather than 16 months may allow greater efficiency of meat production.

Deer carry 50%more muscle than sheep, much of it in their well-priced haunch. Cahes deposit little fat until half grown: adults lose their summer fat during the rut and winter. The lean character of venison well matches modern consumer requirements.

The mineral base of the soils in Islay, Tiree, Coll and the Outer Hebrides is composed mainly of erosion products of Lewisian and Torridonian rocks, together with materials taken from solution in the sea biotically, and subsequently deposited in the form of shell-sand on the windward coasts. The soils composed for the most part of erosion products are acid, and those of marine products basic. Along transect lines at right angles to the coast there is in many places a wide range of soil conditions from calcareous sand to peat, in distances of about 1 kilometre.

The distribution of the Lumbricidæ, a group known to be affected by pH, available calcium content, and moisture content of the soil, is studied within this range in soil types. Seventeen species are involved, three of which are grouped (in numerical considerations) owing to taxonomic difficulties, and these are described in groups living in the main ecological zones of the soil habitat. Relationships are found between the abundance of those species and soil types.

The occurrence of earthworms in three different soil niches—open soil, in and under cow-pats, and under stones—is described, and niche preferences of the dominant species discussed.

The physiology of three nitrate respiring bacteria, identified as Klebsiella strain K312, Pseudomonas strain P388 and Vibrio strain V25, obtained from Kingoodie Bay sediments in the River Tay by enrichment techniques, have been studied in continuous culture. In glycerol limited anaerobic cultures Klebsiella K312 produced NO2 as the primary product of nitrate reduction whereas under N-limited conditions NH4+ was excreted into the culture medium. Nitrate reduction in this organism was accompanied by the synthesis of a paniculate nitrate reductase (NR) whilst under N-limitation a soluble nitrite reductase (NiR) was also produced. In contrast, Pseudomonas P388 dissimilates NO3 directly to gaseous products under anaerobic conditions and was associated with the synthesis of a particulate NR and under N-limited conditions a NiR. Nitrite never accumulated as an intermediate. Vibrio V25 would only reduce NO3 as far as NO2 and was therefore restricted in its use of NO3 under anaerobic conditions. Klebsiella K312 was the most versatile of the three organisms studied and since Klebsiella spp were found in significant numbers in the Kingoodie sediments they may account in part for the high interstitial NH4+ levels found there.

The magmatism early in the Tertiary period resulted in (1) eruption of extensive plateau lavas (Skye, Small Isles, Mull) and of Central-Group lavas (Mull, central Arran), and (2) emplacement of central intrusion complexes (Skye, Rhum, Mull, Blackstones Bank, Arran), of sill complexes (northern Skye, Shiant Isles, western Mull, southern Arran) and of dyke swarms (almost all of the Inner Hebrides) focused on the central intrusion complexes. Each of these magmatic stages and the rock types formed are described, with particular emphasis on the central intrusion complexes and the fact that the centres about which intrusion occurred shifted with time. Some of the causes of compositional variation among rock types are briefly discussed. Most of the magmatism occurred between 61 and 58 million years ago when rifting and separation of eastern Greenland and north-western Europe was initiated.

The epidemiological approach to the investigation of breast cancer is briefly described with special reference to case-control and cohort studies. Risk factors for breast cancer are then reviewed, paying particular attention to menstrual and reproductive factors and to body weight. Some of the hypotheses which attempt to draw the epidemiological observations together are also outlined.

The effects of exposure to exogenous oestrogens are considered in more detail. There is evidence from one study that the administration of large doses of stilboestrol during pregnancy increases breast cancer risk after a latent interval of about twenty years. Conjugated equine oestrogens administered to postmenopausal women may also slightly increase breast cancer risk after prolonged use. Little information is available about the effects of any other type of “hormone replacement therapy”. Combined oral contraceptives do not appear to have any general effect on breast cancer risk, but prolonged early use, especially use before first term pregnancy, may be harmful to the breast.

The herring population inhabiting the Firth of Clyde has supported an important fishery for hundreds of years. The basis for this fishery was until recently a stock of spring-spawning herring which spawn on Ballantrae Bank in the period February-April and which was investigated intensively by means of larval surveys from 1958 to 1979, when it had decreased to a very low level. In the late 1960s there was evidence of a change in the composition of the landings and during the 1970s and in the present decade the majority of fish caught have been of autumn-spawned origin. There is no evidence of significant autumn-spawning in the Firth of Clyde and autumn-spawning herring in advanced stages of maturation appear to leave the Clyde, returning by the time the fishery opens the following spring.

The spawning origin of autumn-spawned herring in the Clyde has been investigated by tagging experiments, and recaptures have been made in the Irish Sea, off the northwest Irish coast and further north along the west coast of Scotland. However the spawning area of the majority of the fish is unknown.

The herring fisheries in the Clyde, originally carried out by ring-net and anchored drift-net but now mainly by pair-trawl, have been managed by closed seasons and in the past few years by total allowable catch regulations under the control of the European Community.

There is also a population of sprats in the Firth of Clyde which supports a small fishery and spawning of this species takes place earlier in the Clyde than elsewhere around Scotland. Mackerel also make annual incursions into the Clyde and support a small summer fishery. Factors affecting the abundance of pelagic fish species in the Clyde are discussed.

The volcanic island of Surtsey in the Westmann Islands, Iceland, was formed by a series of submarine eruptions from 1963 to 1967. It is a natural area, giving scientists the opportunity to study the biological succession without interference from man. In 1972, the occurrence of micro-fungi in soil samples gathered at different locations on the island was assessed by counting and identifying the fungal colonies growing out on different agar media, containing various amounts of soil extract.

Spruce plants (one clone of Picea abies (L.) Karst.) were exposed in environmental chambers to different levels of ozone for 42 days to study the influences of enhanced ozone on root tip chromosomes directly after fumigation had ceased. No visible symptoms resulted from these treatments. The classification of chromosomal aberrations was used as a method to characterise the influences on the root tips caused by ozone. In comparison to the control the fumigated variant showed an increased number of chromosomal abnormalities. Another clone of Picea was used to investigate the ‘post-fumigation long-term effect’ in the genetic material caused by enhanced ozone. These clonal trees appeared to be relatively ozone-sensitive, as pigment reduction and chlorotic spots were observed directly after fumigation had ceased. The spruce trees were also exposed in environmental chambers to different levels of ozone for 24 weeks and then they were transferred to a field near the Institute. Some 21 months after the fumigation had ceased those trees that had been fumigated showed an increased number of chromosomal aberrations compared with the control.

The observed chromosomal abnormalities in all the variants of the experiments consisted of chromosomal ‘stickiness’, chromosome breakage, and fragmentation.

Sand dunes occur extensively around the coastline of Great Britain and in a wide variety of forms. Management for nature conservation is influenced by a long-term historical perspective which has led to a continued policy of protection. It has aimed firstly to prevent damaging developments such as building and orestry, and secondly to control excessive erosion brought about predominantly by man's own activities. However, an assessment of current nature conservation management problems suggests that at many sites in Great Britain over-stabilisation may be as much a problem as erosion. The implications for management in the face of other competing demands is discussed.

An account is given of the benthic harpacticoid copepods of a medium grade subtidal sand at a depth of 8–5 m (below chart datum) off the Ayrshire coast at Hunterston. It is the first account of seasonal changes in subtidal harpacticoids in the Firth of Clyde.

Most of the population is restricted to the top 1 cm layer of sand and this is considered to be related to food availability. There were considerable variations in total densities with largest numbers occurring in late June, as seawater temperatures increased rapidly towards the summer maxima.

Two species examined in detail, Asellopsis hispida and Harpacticus flexus each had one distinct period of reproduction during the year. Gravid females appeared first during the coldest months (January and February) followed by large numbers of copepodites from late April to June, culminating in large numbers of adults in June. Adult males clasped female stages only in May and June, after the main period of egg production. It is thought that viable sperm is carried by the adult females for about six to seven months, supposedly until the next period of egg production the following year. Adults of Harpacticus flexus are thought to be an important source of food for juvenile and small fish, particularly during July.

Present knowledge of long-term changes in benthic species in the Firth of Clyde is reviewed.

Recent work on the annual variations in seasonal cycles of the sand-dwelling bivalve Tellina tenuis da Costa shows some correlations with natural and man-made variations in seawater temperature. Between 1973 and 1984 inclusive good settlements of young occurred on the two beaches examined in the autumns of years when higher mean seawater temperatures occurred in June and July. The implications are discussed in relation to cycles of climatic change. In general, settlements at Hunterston, a thermally enriched area, were considerably greater than at Kames Bay, a site affected only by natural temperature changes. However, T. tenuis at Kames Bay grew to much larger maximum sizes than at Hunterston, except in 1979, when Hunterston animals were larger. The possible interactions of food availability and the modifying effects of heated discharges are discussed.

Earlier results by Dr A. C. Stephen between 1926 and 1951 are reassessed in the light of present knowledge.

The world's oceans continue to play a vital part in man's history on this planet. There is no doubt that in the long process of evolution man's early ancestors left the sea for the land. There is evidence too that some of these having progressed to the mammal stage returned to the sea to produce the dolphins, whales and seals. Some biologists believe that man's predecessors did likewise. Being driven by a shortage of food, they ventured into the shallow coastal waters to collect shell fish and other accessible sea food. During this period they lost much of their fur and learnt to swim. Unlike the aquatic mammals, they remained land animals. It must also be assumed that primitive man developed a great fear of the sea which remained with him even after he had developed the use of boats. Its storms, its vastness, its tides and its currents must have filled him with awe. Even in modern times seafaring occupations are considered hazardous pursuits and drowning as a cause of death is greatly dreaded. In the simple man's mind the dark ocean depths with unpredictable moods of violence create a sense of fear subconsciously supported by the fact that the newly born human being emerges from the dark and watery confines of the womb wherein it has, in its development, recapitulated the pattern of man's evolution. To return to explore the sea would be to retreat into the timeless past. It is not surprising, therefore, that extensive exploration of the sea and sea bed has lagged behind the extension of man's activity over the great land masses, the conquest of the highest mountains, the development of flight and in later years the conquest of space.

When the Royal Society of Edinburgh was founded, the art of beer brewing had already been practised for well ov,er five thousand years, initially in Mesopotamia, then in Egypt and, for the last two millennia, in Continental Europe and in Britain. The procedures used were —and still are —essentially simple. First, barley is malted by growing the grain to allow it to form an assortment of enzymes, some of which, particularly the proteinases and β-glucanases, gradually free the starch granules of the endosperm from their enclosing organic matrix. The enzyme-amylase is also synthesised during malting and, though it has a limited action on the starch in the intact grain, it assumes major importance later during mashing. As a result of the enzymic activity during malting, the endosperm becomes friable instead of tough and the germinated barley, now known as malt, is kiln-dried so that it can be safely stored.