Stable isotopic ratios (mainly 18O/16O, but also D/H) have been measured for the three most important types of late-Hercynian granites, and their hosts, in the western area of the Central Iberian Massif (CIM), Spain. These granites are amphibole-bearing biotite granites, biotite granites and cordierite-bearing biotite granites. No intrusive relationships have been observed among them; the contact of each granite with the others is always gradational. Host-rocks are Precambrian/Cambrian metasediments, ranging from low-grade schists to migmatites (nebulites).

Whole-rock δ18OSMOW values are as follows: amphibole-bearing biotite granites 8·9 ± 0·58% (1σ, n = 17); biotite granites 9·0 ± 0·35% (1σ, n = 11); cordierite-bearing biotite granites 9·6 ± 0·24% (1σ, n = 21). δ18O values for nebulites, into which some of these granites were emplaced, are significantly higher, at 11·1 ± 0·58‰ (1σ, n = 13). The Precambrian to Cambrian shales gave an average value of δ18O = 11·9 ± l·23‰ (lδ, n = 5). Whole-rock oxygen isotope ratios indicate that the origin of the granites was in neither purely sedimentary/metasedimentary rocks nor pristine mantle melts. δ18O values close to 9·0‰ require a crustal protolith, having an important recycled component.

Oxygen isotope results are compatible with the cordierite-bearing granites being generated by assimilation of nebulite-like material by a biotite granite magma. However, 18O/16O of mineral separates obtained from the three different granites and the nebulite indicate that isotopic equilibrium, if ever reached, has not been preserved. The modified isotopic equilibrium is attributed to fluid activity, but mineral-pair δ-δ plots suggest that the granite system behaved as a closed system, and that the fluid was deuteric (magmatic) in origin. This implies that if assimilation did happen, it occurred at a temperature higher than the closure temperature of the different minerals to isotopic exchange. In a δ18O vs δD plot, hornblende and biotite separates from the granites plot within the igneous field. A simple mesocrustal anatectic origin for the peraluminous late Hercynian granites of the western area of the CIM is difficult to sustain on the basis of the stable isotope data, consistent with other field, petrographic and geochemical evidence. Cordierite in the cordierite-bearing granites is not “restitic” from a deep source area, but rather is xenocrystic from the high-grade metamorphic country rock (nebulites).

The structures and mineralogy of the Tertiary ultrabasic and basic intrusions are described. The ultrabasic rocks are thought to be remnants of a layered intrusion which once extended from Hirta to Boreray, and which probably formed by crystal accumulation. The eucrites may represent higher levels of this intrusion. A 350 feet-thick, fine-grained margin is described from the East Glen Bay Gabbro. The metamorphism of the ultrabasic and eucritic rocks, and the formation of the Glacan Mor Complex, probably occurred in a basic environment, before intrusion of the first acid rocks on St. Kilda. Five major-element and twenty-two trace-element analyses are presented.

Faunas of disarticulated ossicles, particularly columnals, are a potentially important source of data for helping to elucidate the patterns of evolution and extinction shown by pelmatozoans in the late Ordovician. The columnal fauna of the Hirnantian High Mains Formation, Craighead Inlier, Strathclyde, includes the following morphotaxa: Cyclocyclicus (col.) foraminosus sp. nov.; Cyclocyclicus (col.) periogmos sp. nov.; Hypsinomocrinus (col.) lewisi gen. et sp. nov.; Tetragonotetragonalis (col.) girvanensis sp. nov.; and Pentagonopentagonalis (col.) sp. This is the first Hirnantian columnal fauna to be described from the North American province; it is distinctly different from Hirnantian columnal biota described from Wales and Kazakhstan.

Studies of the growth stages of some species of Promicroceras (Currie, 1942 and 1943) have led to similar inquiries into the growth stages of other genera. The choice of genera studied has been determined mainly by the material available; but fortunately the material available has provided an opportunity for investigation of a compressed fairly involute form (Witchellia) and some depressed involute forms (Cadoceras and some Sphaeroceratids) for comparison with the evolute Promicroceras.

Most of the specimens used are from a collection of ammonites kept for study by Professor A. E. Trueman, to whom the writer is again indebted for material. Other specimens used are from the collection of the Hunterian Museum, Glasgow University. As usually happens in investigations of this kind, a number of the specimens cut had to be discarded owing to the structure being obliterated by calcification. As a result, the number of measurable sections available was smaller than one had hoped.

Among the interesting specimens which have been yielded by the material of Calciferous Sandstone age (Culm), from Pettycur, near Burntisland, are a petiole of Dineuron and a very small species of Botryopteris. The former genus does not appear to have been previously discovered in Britain, and the present species is, as far as I am aware, only represented by a single example. The Botryopteris, in the form of fragments of petioles, is not infrequent, but its stems are of much more rare occurrence.

Since the ‘Grain to Green Program' was launched in 1999 in the Loess Plateau, China, the processes and patterns of ecological change have become important. Through the use of the fractional vegetation cover (FVC) index, this study examines the spatial distribution and temporal change of vegetation cover in the Loess Plateau during 2000–2014. Over this period more than 60% of the Loess Plateau has remained with little vegetation cover (FVC <30%). The spatial distribution pattern shows an overall increase from the NW to SE. Temporally, the vegetation cover exhibits a general trend of improvement. In 2000–2005, 2000–2010 and 2000–2014, the percentages of restored vegetation (vegetation with significantly increased FVC, P<0.05) were 2, 21 and 52%, respectively. The rate of vegetation cover restoration was highly variable among different bioclimatic zones. The expansion of restored vegetation was greater in the N of the Loess Plateau than in the south. Both human restoration activities and climatic fluctuation influenced the vegetation cover change. The ‘Grain to Green Program' emphasised vegetation restoration. Regional precipitation also had clear effects on vegetation cover. The results of this study reveal that vegetation change shows a non-linear process in response to climate and ecological restoration measures, and that the change gradually emerges over time. This study highlights the importance of considering the spatiotemporal variability in vegetation cover during the implementation of restoration programs, which could aid decision-making for the effective and sustainable management of large-scale restoration programs.

Selaginella grandis, a native of Borneo but now widely grown in Botanic Gardens, was first described by Moore (12). It presents a number of points of considerable morphological interest which have been briefly described by various writers including Goebel (6, 7, 8), Harvey-Gibson (9, 10), Seward (13), Uphof (16), and Worsdell (18). So far as I am aware, however, no full account of the morphology of this species has hitherto been published. My attention was drawn by Professor Drummond to certain abnormal developments exhibited by the plants growing in the Botanic Garden of Glasgow, and, in an endeavour to interpret these, I was led to investigate the normal morphology of this species. Accordingly, in this memoir, the normal morphology will first be described, after which the variations from the normal and certain experimental results will be considered.

The glaciation of East Lothian has already been dealt with separately by Professor John Young, who, when attached to the Geological Survey, treated this subject in the memoir of the district published in 1866. His account of the phenomena, striæ, boulder clay, dry valleys, etc., is concise and clear, but he does not enter deeply into a discussion of causes. A guarded reference to submersion to account for the presence of an erratic boulder of carboniferous sandstone at a height of 1500 feet above sea-level shows in fact that he had not arrived at a full conception of the possibilities involved in glaciation by land ice. He was, however, quite definite in ascribing many important erosion effects in the district to the work of an “ice-stream.” In this as in most other points he had been forstalled by Sir Archibald Geikie, who had already described the immediately adjoining area to the south.

During a visit to the Isle of Bute in the summer of 1920 I took the opportunity of collecting a number of the smaller Oligochæta on the shore at Ascog, and in a pond on the hill just above the village. An account of this collection is given in the present paper; I have also added notes on a few species I have met with since then near Edinburgh. For laboratory accommodation at Ascog I have to thank Prof. L. P. W. Renouf, at that time Superintendent of the Biological Station, who very kindly placed the resources of the institution at my disposal.

Sulphur isotopic data are presented for the four horizons of stratabound mineralisation in the Argyll Group Dalradian (Vendian) of the Central Highlands of Scotland. The styles of mineralisation reflect the stratigraphic and tectonic evolution of the Dalradian basin. The SEDEX-type Ba + (Zn + Pb) Loch Lyon Horizon has δ34S values for pyrite of +17% and for baryte of +27%. The baryte sulphur source was Dalradian sea-water although the values were modified by isotopic exchange with an H2S-rich metamorphic fluid derived from the surrounding graphitic schists. The sulphur source for sulphide in the horizon was probably the underlying strata; sulphide values were only slightly affected by metamorphism. Sulphides in the Pyrite Horizon are isotopically indistinguishable from those in the remainder of the volcanogenic Ben Lawers Schist Formation (0 ± 4%); these values suggest that, at least in the Tyndrum area, sulphides in the Pyrite Horizon are of igneous origin. VMS-type Cu + Zn + Pb mineralisation in the Ben Challum Quartzite Formation has a narrow range of values around + ll%. The likely source of this sulphide sulphur is reduced sea-water sulphate, the isotopic values remaining consistent owing to the buffering effect of anhydrite in the underlying calcium-rich rocks.

Perhaps the most interesting feature connected with the Old Red Sandstone formation in Shetland is the evidence of prolonged volcanic activity in those northern isles. The great development of contemporaneous and intrusive igneous rocks, which gives rise to some of the most striking scenery in Shetland, is all the more important when compared with the meagre records in the Lower Old Red Sandstone of Orkney and the Moray Firth basin. Not till we pass to the south of the Grampians do we find evidence of a far grander display of volcanic action during this period, in the sheets of lava and tuff in the Sidlaws and Ochils and in the great belt stretching from the Pentlands south-westwards into Ayrshire. The relations of the Shetland igneous rocks are admirably displayed in the various coast sections, especially in the mural cliffs of Northmavine and some of the Western Islands. From these records, though they have been subjected to much denudation, it is possible to construct a tolerably complete sketch of the volcanic history of this formation, as developed in that region.

On 17 July 1983 heavy rainfall resulted in a flash-flood in the headwaters of the West Grain, a small stream tributary to the River Wear in the northern Pennines. Associated with the flood was a series of three boulder-lobes. The morphology of these lobes and the associated sediment facies are described and used to estimate the hydro-dynamic mode of transport and deposition. Estimates of the shear-strength and viscosity are consistent with the initial conclusion (based on the sedimentology) that the deposits represent low-viscosity debris-flows. The boulder snouts moved as inertial grain-flows with an associated pebbly-core exhibiting a degree of matrix strength imparted by intergranular friction. A degree of reworking of the upper surface of the core by fluidal flow during core motion and immediately upon deposition was also identified. The full sedimentary sequence therefore represents debris-flow core deposits subject to low dispersive pressure evolving into fluidal debris-torrent deposits.

Chondrichthyan teeth from a new locality in the Scottish Borders supply additional evidence of Early Carboniferous chondrichthyans in the UK. The interbedded dolostones and siltstones of the Ballagan Formation exposed along Whitrope Burn are interpreted as representing a restricted lagoonal environment that received significant amounts of land-derived sediment. This site is palynologically dated to the latest Tournaisian–early Viséan. The diverse dental fauna documented here is dominated by large crushing holocephalan toothplates, with very few, small non-crushing chondrichthyan teeth. Two new taxa are named and described. Our samples are consistent with worldwide evidence that chondrichthyan crushing faunas are common following the Hangenberg extinction event. The lagoonal habitat represented by Whitrope Burn may represent a temporary refugium that was host to a near-relict fauna dominated by large holocephalan chondrichthyans with crushing dentitions. Many of these had already become scarce in other localities by the Viséan and become extinct later in the Carboniferous. This fauna provides evidence of early endemism or niche separation within European chondrichthyan faunas at this time. This evidence points to a complex picture in which the diversity of durophagous chondrichthyans is controlled by narrow spatial shifts in niche availability over time.

Jan Mayen, so far as at present known, is entirely volcanic in origin. The rocks, therefore, are conveniently grouped with the Tertiary and later volcanics of the Faroes, Iceland, and Scoresby Sound in East Greenland. It should be noted, however, that these three localities are linked together by the Faroe-Iceland Ridge, the water everywhere being shallower than 500 fathoms. Jan Mayen, on the other hand, though lying at the same distance from Iceland as the Faroes, is not on the Ridge, and is separated by depths of over 1000 fathoms. Its position is somewhat to the west of the centre of the Norwegian Sea, and at no great distance from depths exceeding 2000 fathoms.

In the first part of this memoir I described the structure of the corpuscles at a stage of larval development when the red cells were actively dividing and the blood contained several varieties of white cells. During the course of these more strictly cytological observations, it was impressed upon me that the great size of the elements and their very marked histological characters, combined with the simple character of the organisation of the animal, made Lepidosiren a very favourable case for the study of the first principles of Hæmatogenesis. I was specially interested in what may be termed a middle phase in the history of the blood. I refer to a period after the primitive corpuscles have acquired haemoglobin and there are leucocytes present, but before the blood-forming organs are unfolded. This stage lasts a relatively long time in Lepidosiren up to the differentiation of the spleen, as the liver takes no part in blood-formation at any period.

The shallow synclinal fold termed the Dalmahoy syncline is situated between the north-western flank of the Pentland Hills and the Murieston fault, the most southerly of the five important easterly and north-easterly dislocations which traverse the oil-shale field of West Lothian. The core of the syncline is occupied by rocks belonging to the lower division of the Oil-Shale Group of the Lower Carboniferous. Intervening between these and the Cement-stone Group is a volcanic zone, probably on the same horizon as the Arthur's Seat lavas, consisting mainly of mugearites and basalts which show their greatest development in the Corston Hill district. Along the whole of the southern limb of the syncline is an extensive spread of Upper Old Red Sandstone, but this formation is almost entirely cut out in the northern limb by the Murieston fault, appearing only in the core of a small anticline near Selms.

Several specimens of myriapodous arthropods have been discovered at the early Carboniferous East Kirkton site near Bathgate, West Lothian, Scotland. None is particularly well preserved, but they are the earliest known Carboniferous myriapods, filling the time gap between the Old Red Sandstone of the early Devonian and the abundant myriapod faunas of the late Carboniferous (Pennsylvanian). One of the specimens, a milliped, provides the earliest evidence for both ozopores (repugnatorial gland openings) and spiracles. A second milliped specimen has some characteristics of the living Order Glomeridesmida, and hence of Enghoff's (1990) ‘ground plan’ of chilognathan millipeds. Aspects of these forms and a third suggest a novel early Carboniferous fauna clearly different from both earlier and later ones. The taxon name ‘Myriapoda’ should be abandoned, since it covers a group now recognised as paraphyletic. ‘Archipolypoda’ is probably synonymous with Order Euphoberiida, Class Diplopoda.

Since the report on the Hydroids collected by the Scotia was completed, almost three years ago, I have had an opportunity, thanks to the kindness of Dr W. S. Bruce, of looking through the enormous mass of material brought together by him during his Antarctic voyages. The search, begun in the hope of finding a few minute species—which, since many are epizoic on other forms of marine life, might readily be overlooked on cursory examination—has resulted in the addition of no less than 25 forms to the 36 already recorded. Deducting from this total of 61 forms two varieties, it appears that the Scotia collection contains in all 59 distinct species. Few, indeed, of these have been obtained in truly Antarctic latitudes—subantarctic or temperate seas having furnished the greater number—but this result is in accordance with the findings of the majority of the recent Antarctic expeditions. Dr Billard, in summarising the results of the Belgian, Swedish, and French expeditions, states that the known Hydroid fauna of Antarctic regions comprises only 32 species. But from his list he has, I think unjustly, excluded South Georgian records. His list, moreover, published before the valuable paper by Professor Hickson and Mr Gravely on the Discovery Hydroids was issued, necessarily makes no reference to the large number of forms recorded by them from Victoria Land.

The development of the Midland Valley of Scotland from Silurian times is re-examined. Earlier (Cambro-Ordovician) terrane accretion of the Midland Valley Terrane to the Laurentian continent by sinistral strike-slip continued to control basin development, sedimentary facies distribution and deformation from Llandovery through to at least early Devonian times. A widespread Mid- to Late-Wenlock strike-slip event has been recognised. This event is variable in its effect, but may indicate a direct link between the Midland Valley, Southern Uplands and Grampian terranes, suggesting that the terranes were juxtaposed by Mid-Wenlock times. In the Midland Valley this event was followed by a renewed phase of basin development with the deposition of ?Pridoli-Lower Devonian clastic sediments which was interrupted by the Lower Devonian volcanic event. There was a shift northwards in the focus of Lower Devonian basin development which was accompanied by a diachronous deformation event across the Midland Valley which resulted in inversion/uplift from early to middle Devonian times. This phase of deformation, uplift and erosion may be related to end-Caledonian transpression.