The Precambrian basement on the islands of Islay, Colonsay and Inishtrahull comprises a deformed igneous association of mainly syenite and gabbro, with minor mafic and felsic intrusions. This association is collectively referred to as the Rhinns Complex. Isotopic data indicate that the complex represents new addition of material to the crust at c. 1·8 Ga. The igneous protolith was juvenile mantle-derived material, not reworked Archaean crust. Overall, the complex has an alkalic composition, with major and trace element patterns similar to igneous rocks generated in a subduction-related setting: high LILE/HFSE and LREE/HREE ratios, together with negative Nb, P and Ti anomalies.

The formation of the Rhinns Complex was contemporaneous with the Laxfordian tectonothermal cycle in the Lewisian Complex. These Proterozoic events are most likely associated with an extensive 1·9–1·7 Ga mobile belt around the southern margin of Laurentia-Baltica. As part of this belt, the Rhinns Complex forms a link between the Ketilidian province of South Greenland and the Svecofennian of Scandinavia.

Inherited isotopic signatures in the Caledonian granites on the north side of the Highland Boundary Fault may reflect the presence of a large area of Proterozoic basement (?Rhinns Complex) beneath Scotland and NW Ireland. Alternatively, the Proterozoic signature could be derived from the incorporation of Moine or Dalradian sediment into the granitic magmas.

We have already referred in the second part of this series to the opinions held by various authors as to the systematic position of the genera Thamnopteris, Bathypteris and Anomorrhœa, and have given in detail the reasons that have induced us to adopt these names for the specimens included in these genera (cf. Part II., p. 213). It is therefore unnecessary for us to deal any further with the historical aspect of the matter in the present communication, and we will at once proceed to the description of the structure of the Fern stems in question.

The first three parts of this work, on the skeleton and muscles, were published in the Transactions of the Society in 1905, 1907, and 1909.

In 1905 I briefly drew attention to the existence of vascular papillæ on the afferent branchial arteries of Myxine, which had up to that time escaped notice, and which I then described in the following words: “In addition to the definite bloodvessels, Myxine possesses a system of large lacunar spaces, such as the extensive subdermal cavity, the spongy tissue of the head, the peribranchial sinuses, etc., which have been generally regarded as belonging to the lymphatic system. I have, however, long been convinced that these spaces were in communication with the blood vascular stream.

This memoir is based upon the study of three normal human embryos belonging to the period of development preceding the cleavage of the paraxial mesoderm into the primitive segments, as well as of certain abnormal specimens of the same early period which have yielded valuable corroborative data, but will not be described in detail. Well-preserved specimens belonging to these early stages are very rare, and our knowledge has been, and can only be, built up from the detailed descriptions of isolated cases by the individual observers into whose hands they happen to fall.

This paper is the first of a series of reports on the detailed investigations of the Gelogy of Central Vestspitsbergen arising out of the Cambridge Spitsbergen Expedition, 1949. While subsequent publications will consist almost entirely of new data, the purpose of this paper is primarily to compile information obtained previously. Following the Introduction, there is a review of the published literature as it affects the area as a whole; this has been attempted at length to save repetition in the later chapters and in any subsequent papers. The later chapters include a detailed study of the Carboniferous to Lower Permian of Billefjorden, using unpublished material which has been made available from several expeditions of the Scottish Spitsbergen Syndicate, some results from the Cambridge Spitsbergen Expedition, 1938, and from that of 1949 in so far as they affect this particular study. It therefore represents an original contribution resulting from a compilation and checking in the field of the work of a number of geologists.

The palæontological results are being worked out separately, but within the area, exposures are sufficient to provide a reliable correlation of the Carboniferous to Lower Permian succession recorded in a number of vertical sections. We have found that the very variable facies can best be grouped into the following formations, retaining so far as possible the earlier names:

The major Devonian diastrophism was followed by erosion, deposition, and again erosion in the Devonian. Culm of estuarine facies was then deposited in a basin due to subsequent movements along a great north-south Devonian fault-belt. They rest on the Devonian to the west of the fault-belt and on pre-Devonian to the east. After the Culm, local conglomerates reflect movements along this fault-belt at the western margin, and in the centre of the basin evaporites are developed. Although a number of disconformities can be traced, there is no important unconformity in the basin. The widespread transgressions recorded outside this area, equivalent to the base of the Cyathophyllum Limestones and again to that of the Brachiopod Cherts, are marked within the area by distinct change of facies but no angular relationship of the bedding.

The distribution of these various formations is shown in a geological map to a scale of 1:100,000, which is the first comprehensive topographical and geological map of the whole area to be published.

Soon after the publication of The Origin of Species it was realised by Huxley and others that convincing evidence of the fact of evolution might be obtained by a systematic investigation of the ancestral history and development of the Equidæ. From studying material in the British and other Museums Huxley announced at the end of the ’sixties that he believed “the Anchitherium, the Hipparion and the modern horses constitute a series in which the modifications of structure coincide with the order of chronological recurrence in the manner in which they must coincide if the modern horses really are the result of the gradual metamorphosis in the course of the Tertiary epoch of a less specialised ancestral form.” But this conclusion was soon profoundly modified. When in 1876 Huxley had the opportunity of examining the Yale and other collections of the fossil horses of America, he was satisfied that “we must look to America rather than to Europe for the original seat of the Equine series,” and “that the European Hipparion is rather a member of a collateral branch than a form in the direct line of succession.”

The hibbertopteroid eurypterid genera Hibbertopterus, Dunsopterus, and Cyrtoctenus occur in the East Kirkton Limestone of Bathgate, West Lothian. Most specimens are fragmentary and appear to have been washed into the depositional area with plant debris and tuffaceous sediment. Nearly all of the identifiable material can be attributed to Hibbertopterus scouleri (Hibbert), but two isolated Cyrtoctenus combs, and a femur comparable with Dunsopterus have also been recognised.

New material of Hibbertopterus scouleri (Hibbert) reveals that the posterior legs and telson resemble those of the cyrtoctenids more closely than was previously thought. It is possible that Hibbertopterus, Dunsopterus, and Cyrtoctenus are indistinguishable except by relatively minor characteristics, and that all of the material from East Kirkton Quarry might be derived from a single eurypterid species. However, associations of the diagnostic sclerites which would demonstrate that these taxa are either cogeneric or distinct have not yet been found.

Micro computed tomography has revealed as yet undescribed internal braincase anatomy of the tetrapodomorph fish Gogonasus andrewsae from the Frasnian Gogo Formation, Paddy's Valley, Kimberley Region, Western Australia. The complete material, including the cranial cavities and channels for blood vessels and nerves, reveals several notable features inside the endocranium. The ethmosphenoid unit includes a median capsule, which lies underneath the median postrostral and rostral series. Based on innervation and association with cutaneous vessels, potential electroreceptive function is inferred for this capsule. Several regions of poor ossification, including foramina for the glossopharyngeal and abducens nerves, as well as the apparent suture separating the ethmoid from the sphenoid portions of the braincase, are possibly indicative of early ontogenetic features. Former interpretations of the course for the superficial ophthalmic nerve inside the nasal capsule of Osteolepis and Gyroptychius may be incorrect, with new research supporting a path through the nasal septum, as in Gogonasus.

The history of investigation of the Silurian rocks of the Dunquin inlier, Dingle Peninsula, County Kerry, Ireland is briefly reviewed. The Dunquin Group of upper Wenlock (Homerian) to middle Ludlow (Ludfordian) sedimentary and volcanic rocks is divided into five formations: the Ferriters Cove, Clogher Head, Mill Cove, Drom Point and Croaghmarhin Formations, the last of which reaches the Ludlow and passes transitionally into the succeeding continental Dingle Group, probably largely Přídolí in age. The Dunquin group is of varied shallow marine sediments with a continental episode probably represented in the Mill Cove Formation. The biostratigraphy of the other four formations is considered in relation to a full faunal list. Details of representative sections and exposures are provided. There is brief comment on the palaeogeographical setting of the inlier.

This paper reviews the key evidence for global climate change and outlines the trends of climate change in Scotland, the potential impacts and the implications for policy makers. Human activity is causing a rise in atmospheric CO2 concentrations and there is little doubt that this is contributing to global warming. There is greater uncertainty about how this global trend will play out at a regional scale and also how close we are to climatic tipping points. Instrumental records document the overall trends and variability in Scotland's climate since 1914. These show that since the 1960s, Scotland's average climate has proved to be wetter (especially in the west) and warmer. This trend is expected to continue throughout the 21st Century with, on average, hotter and drier summers and milder and wetter winters. However, extreme events will continue to affect Scotland, as they have always done, and the severity and frequency of these events may increase. Sea levels will continue to rise modestly, especially in the Outer Hebrides and the Northern Isles. Some of the uncertainty in climatic predictions is captured in the probabilistic outputs of Defra's UK Climate Projections 2009 programme. An initial attempt to assess the likely impacts of climate change is provided in Defra's 2012 Climate Change Risk Assessment, which includes a report specific to Scotland. Whilst most of the risks involve negative impacts, with increased flooding and loss of biodiversity being especially adverse, there are also positive impacts with associated opportunities, especially in terms of increased agricultural production and larger numbers of tourists. The report on Scotland will allow different groups of policy makers to refine the risks associated with specific activities. But given the fragile nature of many of the metrics underpinning the report, caution should be exercised in using it to frame climate adaptation strategies.

The first fossil opilioacariform mite (Acari: Opilioacariformes), Paracarus pristinus sp. n., is described from Baltic amber (Tertiary: Eocene). This well-preserved inclusion has six eyes and, thus, can be excluded from the derived, four-eyed genera. Based on characters such as the extremely long leg 4, it is assigned to the extant central Asian genus Paracarus Chamberlin & Mulaik, 1942. As with many Baltic amber inclusions, we lack an exact provenance for the type specimen, but the Baltic region is further north than the present day range of Recent opilioacariform species and suggests that the range of this group was once more extensive within Eurasia. The first solifuge (Solifugae) from Baltic amber is described as Palaeoblossia groehni gen. et sp. n. Based on its size and general appearance, it can be assigned to Daesiidae, and again represents an arachnid group which previously had a much wider geographical range. If adult, it may represent the smallest solifuge known.

The migmatite complex of the Savonranta district of eastern Finland represents the combined effects of polyphase deformation, polymetamorphism and the emplacement of a series of dioritic, grandioritic, granitic and pegmatitic masses. The most significant feature in terms of both regional structure and control of neosome emplacement is a large wrench fault zone along which there has been a minimum of 30 km displacement. Its development was controlled by a stress system related to plate movement in the early-middle Proterozoic Svecokarelian orogenic belt.

Successive neosome development has been related to the extensive structural and metamorphic history of the amphibolite facies palaeosome mica schists which has been deduced from refolding and cross-cutting relationships. Rb–Sr whole-rock isotopic studies of a porphyritic granite, whose emplacement was controlled by the wrench fault regime, indicate an age of crystallisation of 1786 ± 80 m.y. The initial 87Sr/86Sr ratio of 0·7053 ± 01 shows the source region for the granite magma had a previous crustal history.

In all vertebrates, as the embryo develops at one pole of the egg, it sinks inwards till it becomes completely enclosed in a hood or sac filled with fluid, the amnion. When the sac or true amnion has completely closed over the embryo, it becomes separated from the outer layer, which remains in contact with the covering of the egg as the false or chorionic amnion.

A description is given of the hydrological regime and associated surface water quality recorded at a multi-disciplinary long-term investigation into the effects of acid precipitation and afforestation. The study catchment at Loch Dee is situated on the margins of the Loch Doon granite complex in SW Scotland. Annual rainfall is in excess of 2200 mm. The three main tributary burns exhibit a rapid response to rainfall with a high percentage of direct runoff. The loch with an average volume of 3650 M1 and a contributing catchment area of 15·6 km2 has an average turn-over of approximately forty days but this has varied from 15 to 100 days. Local physical variations are shown to influence both hydrological response and surface water quality. Generally stream water during spate conditions reflects rainfall chemistry. Occasionally, however, moderately acid rainfall containing large concentrations of sea salts has produced highly acidic runoff through a process of ion-exchange within the surface horizons of the soils. The quality of base flows shows a spatial variation which reflects various lithologies to the extent that pH values ranging from 4·9 to 6·9 have been observed.

The following paper deals with an investigation of the successive zones of plant remains contained in the deeper peat deposits covering areas in the Scottish Southern Uplands. The field work was carried on during the summer and early autumn of 1904, and the detailed examination of the peat in the laboratory during part of the winter. No attempt has been made to work out the detailed flora of the different zones, but attention has chiefly been directed to the dominant plant remains found at different horizons in the mosses. Whilst the list of plants from each zone is small, the general facies of the flora of any layer can be gauged from the abundant presence of a few characteristic plants such as Salix reticulata and Empetrum, or Sphagnum and Eriophorum. Thus, while the investigation is incomplete as regards any addition to the history of the British Flora, it will, I hope, throw some light upon the succession of vegetation over the older peat mosses since their origin.

Radiometrie evidence suggests a complex evolution for some parts of the Moine assemblage NW of the Great Glen fault in Scotland. Four generations of microdiorite sheet intrusions are distinguished and used as time- and strain-markers in this region. Two are found to record different tectonic episodes in the Morar and Glenfinnan divisions and their Loch Eil division cover during the c 750 Ma Knoydartian orogeny. These demonstrate that F1 and F2 (of the Grenvillian orogeny) and F3 folds (of the Knoydartian orogeny) in the Morar and Glenfinnan divisions are absent from the Loch Eil division. Two later generations of microdiorites record successive episodes (F4 and F5) of the c. 455 Ma Caledonian orogeny.

The tectonic history of the region is considered after a discussion of the use of microdiorite sheet intrusions as strain-markers. This is because, rather than fold or boudinage, they deformed as incompetent single layers and foliated, mullioned or thinned uniformly instead. The attitudes of different elements of the microdiorites and their internal foliation are used to construct strain ellipsoids for four tectonic episodes on scales of 4–400 m and >4000 m. Three of these episodes are found empirically to have involved irrotational plane strain and all are close to coaxial even though the principal axes of strain appear to have swapped one for another in space as well as time.

Changes in Holocene (Flandrian) relative sea levels and coastal geomorphology in the lower Cree valley and estuary, SW Scotland, are inferred from detailed morphological and stratigraphical investigations. A graph of relative sea level changes is proposed for the area. Rising relative sea levels during the early Holocene were interrupted at c. 8300–8600 14C years B.P.(c. 9400–9900 calibrated years B.P.), when an extensive estuarine surface was reached at c. −1 m O.D., after which a fluctuating rise culminated at c. 6100–6500 14C B.P. (c. 7000–7500 calibrated years B.P.) in a prominent shoreline and associated estuarine surface measured at 7·7–10·3 m O.D. A subsequent fall in relative sea level was followed by a rise to a shoreline at 7·8–10·1 m O.D., exceeding or reoccupying the earlier shoreline over much of the area after c. 5000 14C B.P. (c. 5,800 calibrated years B.P.), before relative sea level fell to a later shoreline, reached after c. 2900 14C B.P. (c. 3100 calibrated years B.P.) at 5·5–8·0 m O.D., following which relative sea levels fell, ultimately reaching present levels. During these changes, a particular feature of the coastline was the development of a number of barrier systems. The relative sea level changes identified are compared with changes elsewhere in SW Scotland and their wider context is briefly considered.

Hydrothermal alteration at Rhynie, Aberdeenshire, Scotland, is concentrated along a fault zone, which juxtaposes surface deposits and the mineralised feeder zone to the Rhynie hotspring system. Mineralisation consists of breccias and veins filled with quartz, chert, calcite, K-feldspar and pyrite. Associated pervasive alteration comprises a high-temperature K-feldsparquartz-illite facies (formed at 250–350°C), a medium-temperature mixed layered illite/smectitequartz-K-feldspar-chlorite-calcite facies (formed at 150–200°C) and a low-temperature mixed layered illite/smectite-chlorite-calcite facies (formed at 100 to +150°C). The fluids responsible for mineralisation were mainly moderate- to high-temperature (Th =91–360°C), low-salinity (<0·2 to 2·9 wt.% NaCl eq.) H2O-NaCl-heated meteoric fluids comparable to modern and ancient hot-spring systems. The migration of these fluids was mainly restricted to a major fault zone bounding the Devonian basin. Fluids responsible for mineralisation, alteration and cementation elsewhere in the basin were low-temperature (Th 57 to 161°C), low- to high-salinity (<0·2 to 18 wt.% NaCl eq.) H2O-NaCl fluids, which resemble basinal brines.

Physiographic investigation was undertaken in the coastal belt of the Moray Firth between Golspie and Port Gordon in the hope that it would serve a double purpose. So far as was known no detailed morphological study of any large section of the British coasts had been made, and it appeared that such an investigation upon a varied coast-line would increase our knowledge of marine processes and the work they accomplish. Furthermore, since the area selected includes some of the finest and most complex examples of raised beach at several levels, it was possible by careful attention to heights, absolute and relative, to contribute evidence that may serve in future geological studies of a broader character. The exceptional wealth and variety of features of marine abrasion and deposit in these 250 miles of coast is due largely to the fact that they have been produced on a rising land margin, and so have been preserved.

Vigorous Carboniferous extensional tectonism and associated igneous activity is a feature of Ireland and the neighbouring areas of Newfoundland and Britain. In West Connacht, Ireland, dolerite dikes of late Carboniferous age are newly recognised and distinguished from Tertiary dolerites. In the N, the 320 Ma-old Logmor dike trends N–S across the Ordovician South Mayo Trough, and has an evolved, mildly alkaline basalt geochemistry. In the S, in Connemara, a diffuse and arcuate swarm of ENE–NE trending, 305 Ma-old dolerite dikes, the Teach Doite swarm, cuts the Galway Granite batholith and its envelope of Dalradian gneisses. These more tholeiitic dolerites reveal the mineralogical and geochemical effects of varying degrees of pervasive hydrothermal alteration, imposed on an original magmatic composition similar to that of mid-ocean ridge basalts. Variscan overprinting on k–Ar ages from West Connacht dolerites clusters at 300, 245 and 205 Ma. Overprinting is also a feature of much of the Galway Granite. Carboniferous diking in West Connacht may have responded to nascent opening of the proximate North Atlantic, its pattern related to domal uplift adjacent to the rifted zone.