It is well known that the dimensions of the ammonite shell conform approximately with the properties of a logarithmic or equiangular spiral. An illuminating account of the logarithmic spiral in its application to the growth of molluscan shells is that given by Sir D'Arcy Thompson (1917, pp. 491–586, and 1942, pp. 748–849). His formula relating the spiral angle of the shell and the ratios of certain linear dimensions must be useful to all interested in shell form in molluscs.

The usefulness of restriction fragment length polymorphisms (RFLPs) in plant breeding and genetics is discussed, with particular emphasis on tagging genes, map-based cloning, the assessment of genetic variability and distances, and comparative genome mapping.

The Department of Plant Breeding and Biometry has currently established tight linkages between RFLPs and more than 20 genes of economic importance. Approximately half of these genes confer resistance to major pathogens including nematodes, bacteria, fungi, and viruses. Other genes tagged are involved in various aspects of crop quality.

Locating genes with respect to DNA markers on an RFLP map provides a starting point for cloning the genes by chromosome walking. This strategy is currently being pursued for three disease-resistance genes that have been placed on the tomato RFLP map; Pto (resistance to Pseudomonas syringae), Mi (resistance to root-knot nemotodes) and Tm2a (resistance to tobacco mosaic virus). Further discussion will include the construction of a yeast artificial chromosome library and the collection of additional DNA markers in the regions of interest through RAPD analysis of nearly isogenic lines.

The assessment of genetic variability and fingerprinting varieties based on RFLP data will be briefly discussed.

Comparative genome mapping in the family Solanaceae has allowed the relationships among tomato, potato, and pepper to be unravelled. Tomato and potato share a near perfect conservation of gene order throughout their genomes. In contrast, while pepper shares most of its single copy DNA with tomato and potato, the order of these markers is highly rearranged compared with the other two species.

As a river in its seaward course gathers volume and momentum from its tributaries, so does a science, from its inception to its attainment of maturity and beyond, increase its strength, scope and depth by incorporating into itself its historical past, built up by the contributions of those scientists and philosophers whose work marks stages in its progress. A history of science, to fulfil its purpose, must unravel the intricate strands of ideas and facts which form the fabric of modern science and trace them back to their inspiration and source. Such a history would be almost beyond the bounds of human endeavour, and its only practicable substitute tends to degenerate into a mere collection of names of scientists, combined with a review of their individual contributions to the development of science. Science, however, is neither an assemblage of facts nor of ideas. It is a co-ordinated system of facts linked by theories—with the emphasis, generally speaking, on the ideas—and within our limited capacity it can best be interpreted by reconstructing the lives and reliving the thoughts of those men who have done most to fashion it. Such a man was Isaac Newton and such also was James Hutton. It is of little profit to argue as to which was the greater mind. What Newton achieved in the field of astronomy and mathematics Hutton achieved in the field of geology. It was he who provided geology with a theory: and here we must take theory, not as something remote and opposed to fact, but in its original meaning in Greek, namely, comprehension.

The microbial populations on cereal straw at harvest are characteristic of the phylloplane. Incorporation of straw into soil represents an enrichment disturbance and results in a rapid stimulation of soil microbial activity. The dominant fungal colonists of the straw in soil were found to vary with soil water potential over a twenty-eight week period of incorporation. The dominant fungal genera were Penicillium and Mucor, followed by Gliocladium, Fusarium and Trichoderma. Basidiomycetes were only isolated from straw in a wet (−0.1 MPa) soil. Prior inoculation of straw with Gliocladium roseum (Link) Banier resulted in changes in the dominance of these fungi, particularly in a dry soil. In vitro data on spore germination, germ tube extension and growth of these soil fungi on agar media were not correlated with those on unsterile straw leaf sheaths or sterile straw segments.

Morphology and histology of the males of Acanthobonellia miyajimai (Ikeda) and Acanthobonellia vulgaris Menon and DattaGupta have been described. The males of the two species are large and look alike in all respects. Ciliated epithelium, subepidermal glands and two to four seminal vesicles are characteristics of these worms. The alimentary canal is in the form of a chain of vesicles which appear to be a common feature of Acanthobonellia, Acanthohamingia or Ikedella. Anatomical features have been described and figured.

Published studies on the Coleoptera of the Inner Hebrides from 1853–1981 are briefly reviewed and a full bibliography is provided. This is supplemented with data obtained from museum and private collections, unpublished manuscripts, etc., and the results of extensive surveys undertaken on eight of the islands during 1980 and 1981. Doubtful published records are discussed and records of 716 species are accepted. To these, 221 species have been added as new to the Inner Hebrides, together with numerous new island records. A comprehensive table lists the 937 species of Coleoptera and shows on which of the 15 largest, or best documented islands, they occur. Details of the limited known fauna for three of the remaining islands are also given. Our knowledge of the fauna of the Inner Hebrides remains very incomplete. Only 54% of the species recorded are known from the Outer Hebrides, whilst their faunal relationships with the Scottish mainland cannot be assessed until surveys of similar detail have been done on the west coast.

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.

Both respiration and generation by soybean embryonic axes showed a sharp increase upon germination, leading to a significant increase in the steady-state concentration of and H2O2 after 6 h of imbibition. An assay was developed to assess in vivo generation of reactive oxygen species, based upon DCFH-DA oxidation. Fluorescence of the external medium was dependent on reaction time and axes number and was inhibited by catalase.

α-Tocopherol content declined significantly after 24 h of incubation, as compared to the content at the onset of germination. Incubation in the presence of redox cycling agent paraquat (4 mM) for 24 h increased α-tocopherol content to 1.9±0.2 nmol per axis from 1.0 ± 0.1 nmol per axis in the absence of paraquat. Supplementation of the incubation medium with 500 μM Fe-EDTA increased α-tocopherol content to 1.8±0.1 nmol/axis and DCFH-DA oxidation by two-fold.

The data presented here showed that active metabolism at the onset of germination increased steady-state concentration of oxygen active species and suggest that cellular content of α-tocopherol is physiologically adjusted as a response to conditions of oxidative stress.

The question as to the existence of life at great depths was still a matter of controversy in the last century. In spite of the fact that the remains of living animals were recovered from several hundreds of metres, many marine biologists hesitated to believe that animal life could exist in deep-sea conditions. In 1841, Sir James Clark Ross, the leader of the British Antarctic Expedition, claimed:‘… and although contrary to the general belief of naturalists, I have no doubt that from however great a depth we may be able to bring the mud and stones of the bed of the ocean, we shall find them teeming with animal life; the extreme pressure at the greatest depth does not appear to affect these creatures; hitherto we have not been able to determine this point beyond a thousand fathoms, but from that depth several shellfish have been brought up with the mud’ (Murray 1895, p. 79). Edward Forbes, naturalist on H.M.S.S. Beacon, for instance, referred to the marine environment in excess of 550 m as the ‘azoic zone’. But the classical deep-sea expeditions in the second half of the nineteenth century, among others the famous voyage of the Challenger, produced overwhelming evidence for a more or less abundant abyssal fauna.

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.

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.

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.

Contrary to previous ideas, it is suggested that Harris and the major part of Lewis were covered by a large local ice cap during the last glacial phase. Local glaciers from central Lewis and the interior of North Lewis moving over the eastern fringe across the Eye peninsula and towards the north-west coast appear to have overridden and redistributed deposits from earlier glaciers of external origin. There is some evidence that the northern tip of Lewis and the Tolsta Head peninsula were also invaded by external ice during the final glacial phase. The application of a theoretical icesheet-surface profile substantiates the concept that Scottish mainland ice at its maximum advanced over northern parts of the island. According to the C-14 date of an organic layer beneath glacial till at Tolsta Head the last incidence of external and/or local ice in the island occurred after 27,300 years BP. Deglaciation phenomena at Uig, south-west Lewis, mark an earlier stage in the dissolution of the ice cap, while hummocky moraine in the mountain and submountain zone indicate the retention or renewed formation of valley glaciers during the late Devensian.

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.

In 1942 an experiment was started in order to test the possibility of increasing the fertility of a small sea-loch by the addition of nitrate and phosphate fertilizers, with the view of improving the growth rate and yield of fish. It was based on the well-established fact that the phytoplankton organisms are the main producers of organic matter and therefore represent the main source of food supply in the sea, and that nitrogen and phosphorus compounds are among the important factors controlling and limiting plankton production. It was thought that the addition of readily available plant nutrients would result in an increase of plankton production and thus of the food supply of the bottom-living animals which are fed upon by fish. An increase of the bottom fauna might then result in an improved growth rate of the fish population. Normally most marine fish require about four years to reach marketable size, and the object of our experiment was to find out whether the addition of fertilizers would lead to a shortening of that period and to an improvement of the yield in fish per unit area.

Early investigations into the effects of pressure on marine invertebrates were concerned mainly with determining limits of tolerance to extreme pressures, but within the last 25 years it has gradually emerged that many invertebrates are sensitive to quite small changes in pressure, often less than one atmosphere (1000 mb). The responses of most planktonic animals appear to be of a depth regulatory nature but certain littoral organisms show rhythmic changes in activity in response to cyclical pressure changes of tidal amplitude and frequency. The ecological role of such responses is considered.

The parameters of the pressure sense are known only from behavioural studies and offer little information concerning the process of reception. A possible mechanism of transduction based on the compression of a surface film of gas is described.