Doleritic intrusions known to post-date the obduction of the Ballantrae complex during Arenig times record changing magma provenance during the cooling and serpentinisation of obducted peridotite. There are two groups of dolerites with different petrographical and geochemical characteristics.

The earlier emplaced group, which is subordinate, is characterised by amphibole formed under low metamorphic facies conditions and the virtual absence of Fe–Ti oxides. Chemically these rocks are of primitive tholeiitic character and are similar to modern island-arc basalts. They were derived from a strongly depleted mantle source region. The source region of the later emplaced group, which is predominant, was much less depleted. Clinopyroxene and plagioclase, much of it albitised, are the dominant minerals. Fe–Ti oxides also are common and there are pronounced chilled margins and well-preserved ophitic textures. Although showing mildly alkaline tendencies, these rocks originated from a tholeiitic parental magma of “within-plate” type.

Both groups show evidence of rodingitisation and associated alteration related to serpentinisation of the peridotite. During the metasomatic activity, only some elements were mobile, while Al2O3, total Fe, MgO, TiO2, Cr, Ni, Nb, Y and Zr remained almost constant. Assessment of original magma type and geotectonic environment, and demonstration that both groups of doleritic rocks show the products of fractionation, has relied heavily on data for the apparently immobile elements and on petrographical study which identified those rocks least affected by alteration.

This communication deals with the fossil plants of the Calciferous Sandstone Series and Carboniferous Limestone Series of Eskdale and Liddesdale; of the Lower Coal Pleasures of Canonbie; of the Middle Coal Measures of Byre Burn, Canonbie; and of the Upper Coal Measures, Joekie's Syke, Cumberland; to which is added a list of the fossil plants of the Calciferous Sandstone Series of Cumberland and Northumberland, with the object of comparing them with those from the corresponding series in Scotland.

The record of Ordovician Eurypterida from New York State, USA, is shown to be largely false. Twenty-nine species in 17 genera are here recognised as pseudofossils, reducing by more than 75% the total number of named Ordovician eurypterid taxa. Consequently, 10 families now have their first occurrence either later in the Ordovician or in the Early Silurian. The implications for eurypterid palaeoecology, diversity and evolution are not as straightforward as would be expected from such a drastic taxonomic revision. All Ordovician eurypterids are now known to occur in shallow-water, near-shore shales or fine-grained carbonates. Diversity measures indicate that the end-Ordovician extinction event appears to have had less effect on eurypterids than previously known, and their turnover is level in the Ordovician.

Various selective agents exert their influence on the processes governing the survival of new forms within an established plant group. As the balance of these agents changes so also will the genetic composition of the plant group change. Environmental conditions undoubtedly permit and direct evolution, but apparently the action of the environment is mainly selective in nature, and, although not directly concerned in the production of new growthforms, it aids the survival of suitable forms by establishing a certain amount of genotype isolation. Amongst the various selective agents whose action is confined to the direct selection of genotypes, or phenotypes and therefore indirectly of genotypes, there is the important question of pollination and fertilisation. As the very existence of individuals depends on compatible fertilisation, the investigation of the problem of pollination and fertilisation obtaining within a plant group is essential preparatory to any study of the survival of individuals within that plant group.

A new chasmataspid (Chelicerata: Chasmataspidida) is described from the Early Silurian (Late Llandovery–Early Wenlock) of Lesmahagow, Scotland, as Loganamaraspis dunlopi gen. et sp. nov. It is distinguished from related forms by the low tapering ratio of the postabdomen, pediform sixth prosomal appendage and a heart-shaped metastoma. Additionally, a genital operculum with a genital appendage is preserved. The recognisable morphology of L. dunlopi gen. et sp. nov. bridges some of the gap between the Ordovician Chasmataspididae and the Devonian Diploaspididae. Traces of the gut are reported for the first time from a chasmataspid. Chasmataspids are regarded as sister group to the eurypterids: an anterior opercular plate anterior to the genital appendage in L. dunlopi gen. et sp. nov. is regarded as homologous to the anterior opercular plate of the three-segmented genital operculae of Dolichopterus and Stylonurina. This is considered a plesiomorphic character within Eurypterida, whilst the two-segmented genital operculum (with deltoid plates) of Eurypterina is considered apomorphic.

A series of specimens from the Scottish Limestone Coal Group (Lower Namurian) is described, among which occurs Adelophthalmus cf. wilsoni (Woodward) from West Lothian, a group of specimens from the No. 2 Ironstone of Loanhead, Midlothian, one of which is recognized as belonging to the new species Mycterops (?) blairi, and a prosomal appendage from Lanarkshire which is referred to the genus Hibbertopterus. New evidence is presented on the nature of the prosomal appendages of Eurypterus (?) stevensoni R. Etheridge jr. which is designated the type species of the new genus Dunsopterus. The Coal Measures species Glyptoscorpius minutisculptus Peach is recognized as an eurypterid for which the new genus Vernonopterus is created. The systematics of these and other late palaeozoic genera which have been included by Kjellesvig-Waering (1966) in the families Woodwardopteridae and Hibbertopteridae are discussed.

Acanthodians are represented by numerous young and poorly cranially ossified Acanthodes ovensi White, the earliest known acanthodid. Study of the small A. ovensi together with the type series shows that squamation begins posteriorly, and spreads anteriorly along an initially triangular front, as in A. bridgei Zidek. Gyracanthus sp. occurs at several horizons in the sequence. The coelacanth remains include the first articulated specimen known from Foulden, but preservation only allows an assignment to cf. Rhabdoderma. Although these taxa are distinctive, resemblances to other taxa occur only in generalised features. Hence, unlike the Foulden actinopterygian fish, the acanthodians and coelacanths cannot be used to suggest closer affinities with any other fish of this age, on which information is sparse.

The Foulden Fish Bed was deposited in a semi-permanent brackish water lake on a floodplain between a northerly mountain range and the sea. The lake supported a rich biota mainly of swimming animals (fish and crustaceans) with a benthos of trace fossils only in the earlier and later stages of the lake's development. Xiphosurans are very rare. This biota changed according to the physical conditions of the lake. Salinity, fluctuating according to water level, was a dominant control. Early in the lake's history there was a dominant benthos of euryhaline bivalves; at the same time, large rhizodonts lived in the lake as the top carnivores. Subsequently, crustaceans were the dominant nektobenthos, in a probable brackish-water regime, the rare Bairdops preying on the common Belotelson; there was a limited infauna. Following this, palaeoniscids abound in the middle part of the sequence, perhaps due to a higher water level but crustaceans are absent at this horizon. During the last stages before final silting-up following a mass-mortality episode, biotic diversity reached a maximum with many fishes and crustaceans and some trace fossils, due to optimal salinity conditions.

Comparisons are made with other Carboniferous biotas and with the Jurassic Solnhofen limestone.

Cretaceous and Cainozoic granites and rhyolites in the northwestern U.S.A. provide a record of silicic magmatism related to diverse tectonic settings and large-scale variations in crustal structure. The Late Cretaceous Idaho Batholith is a tonalitic to granitic Cordilleran batholith that was produced during plate convergence. Rocks of the batholith tend to be sodic (Na2O > K2O), with fractionated HREE, negligible Eu anomalies, and high Sr contents, suggesting their generation from relatively mafic sources at a depth sufficient to stabilise garnet. In contrast, Neogene rhyolites of the Snake River Plain, which erupted in an extensional environment, are potassic (K2O > Na2O), with unfractionated HREE patterns, negative Eu anomalies, and low Sr contents, suggesting a shallower, more feldspathic source with abundant plagioclase. Eocene age volcanic and plutonic rocks have compositions transi- tional between those of the Cretaceous batholith and the Neogene rhyolites. These data are consistent with a progressively shallowing locus of silicic magma generation as the tectonic regime changed from convergence to extension.

Permineralised material of Rhacopteris lindseaeformis (Bunbury) Kidston and Spathulopteris obovata (Lindley & Hutton) Kidston, showing both external morphology and excellent anatomical preservation, is described from the Lower Carboniferous (?Asbian, Upper Viséan) tuffs and dolomitic ashes outcropping at Weaklaw–Gullane, East Lothian, Scotland. These specimens provide the first anatomical information on these two well-known plant compression genera. The rachises have Lyginorachis-type anatomy with distinctive characters in the two species. Spathulopteris rachises correspond to Lyginorachis kingswoodense Meyer-Berthaud, previously described from the localities of Kingswood and East Kirkton, whereas Rhacopteris shows similarities with the petiole attributed to Bilignea from Oxroad Bay. Both foliage types conform to seed-fern frond organisation. This new evidence contradicts previous interpretations of Rhacopteris as a fern or a progymnosperm. We suggest that Rhacopteris lindseaeformis and Spathulopteris obovata represent the foliage of some of the arborescent gymnosperms which are found associated in several contemporaneous localities.

This paper reviews the evidence for environmental change during the Lateglacial period (c.14.7–11.7 ka), perhaps the most intensively studied episode in the Quaternary history of Scotland. It considers first the stratigraphic subdivision and nomenclature of the Lateglacial, before proceeding to a discussion of the various lines of proxy evidence that have been used to reconstruct the spatial and temporal patterns of environmental change during this time period. These include pollen and plant macrofossil data; coleopteran and chironomid records; diatom data; stable isotope and geochemical records; and evidence for human activity. The paper then considers the principal methods that have been employed to date and correlate Lateglacial events: radiocarbon dating; surface exposure dating; varve chronology; and tephrochronology. This is followed by an examination of the constraints imposed on environmental reconstructions, an account of the ways in which the evidence can be employed in the development of an event stratigraphy for the Lateglacial in Scotland, and a proposal for a provisional Lateglacial type sequence (stratotype) at Whitrig Bog in SE Scotland. Emphasis is placed throughout on the potential linkages between the Scottish records and the isotopic signal in the Greenland ice cores, which forms the stratigraphic template for the N Atlantic region. The paper concludes with a discussion of the strategies and approaches that should underpin future research programmes on Lateglacial environmental change in Scotland.

In Scotland, the base of the Ballagan Formation has traditionally been placed at the first grey mudstone within a contiguous Late Devonian to Carboniferous succession. This convention places the Devonian–Carboniferous boundary within the Old Red Sandstone (ORS) Kinnesswood Formation. The consequences of this placement are that tetrapods from the Ballagan Formation were dated as late Tournaisian in age and that the ranges of typically Devonian fish found in the Kinnesswood Formation continued into the Carboniferous. The Pease Bay specimen of the fish Remigolepis is from the Kinnesswood Formation. Comparisons with its range in Greenland, calibrated against spores, show it was Famennian in age. Detailed palynological sampling at Burnmouth from the base of the Ballagan Formation proves that the early Tournaisian spore zones (VI and HD plus Cl 1) are present. The Schopfites species that occurs through most of the succession is Schopfites delicatus rather than Schopfites claviger. The latter species defines the late Tournaisian CM spore zone. The first spore assemblage that has been found in Upper ‘ORS' strata underlying the Ballagan Formation (Preston, Whiteadder Water), contains Retispora lepidophyta and is from the early latest Famennian LL spore zone. The spore samples are interbedded with volcaniclastic debris, which shows that the Kelso Volcanic Formation is, in part, early latest Famennian in age. These findings demonstrate that the Ballagan Formation includes most of the Tournaisian with the Devonian–Carboniferous boundary positioned close to the top of the Kinnesswood Formation. The Stage 6 calcrete at Pease Bay can be correlated to the equivalent section at Carham, showing that it represents a time gap equivalent to the latest Famennian glaciation(s). Importantly, some of the recently described Ballagan Formation tetrapods are older than previously dated and now fill the key early part of Romer's Gap.

In recent papers published in the Proceedings and Transactions of the Society the importance of Size as a factor determining the morphology of the vascular system of Pteridophytes has been discussed (2, 3, 29). The purpose of this memoir is to submit data concerning the vascular system of roots, and to determine to what extent Size may have acted as a causal factor in influencing the morphology of these structures. It has been pointed out that the most useful material for these causal studies is to be found where there is only primary vascular tissue, free from complexities such, for example, as the formation of secondary wood. In the case of leafy shoots the vascular system is often profoundly influenced by the insertion of the appendages, especially where the latter are of the megaphyllous type. In many of these instances the resulting vascular structure is due to a complex of so many interacting factors that the specific effect of any one is very difficult to determine. To understand the influence of any one factor in particular we must turn, as Professor Lang has pointed out, to the study of favourable cases (19). These are to be found where the structure is of primary nature, unaffected by the activity of secondary meristems, and where the organ in question is influenced as little as possible by the insertion of appendages.

The Tertiary geology of north-western India is of particular interest on account of the extensive development of richly fossiliferous rocks of Lower Eocene (including Palæocene) age. The monographs by Cossmann and Pissarro (1909a, 1927) and Vredenburg (1928) have familiarised us with the well-preserved molluscan fauna of the Upper Ranikot beds (Palæocene) of Sind, while Lt.-Col. L. M. Davies' collection of mollusca from a slightly lower horizon in the Samana Range, on the North-West Frontier, has recently been described by myself (1930). With the exception, however, of one family, the Gisortiidæ, dealt with by Vredenburg (1927) and Schilder (1930), the mollusea of the overlying Laki group (Ypresian), as well as of the Khirthar group (Middle Eocene), have been neglected by modern workers. The well-known monograph by D'Archiac and Haime (1853–54), moreover, in which some Laki species are described, has always been a source of confusion owing to the fact that fossils from all horizons from the Danian to the Miocene are grouped together as “Nummulitic,” and no reliable information as to their respective horizons has been available.

Some time ago the author published the results of a series of experiments on the flow of water through tubes having uniformly diverging boundaries, in which the loss of energy corresponding to given angles of conicity of the tubes was determined. These pipes, some circular, others square or rectangular in cross section, had the same initial and the same final areas, these being respectively the same as those of circles of 1·5 inch and 3·0 inches diameter, the ratio of initial to final mean velocity of flow being in each case 4 to 1.

That the facts which I communicate regarding the natural history of the salmon in its earlier stages, may not appear altogether undeserving of consideration, I may premise that my remarks have not proceeded from hasty or imperfect observation, but from the experience of many years sedulously devoted to the subject, the whole of my life, with the exception of a few seasons, having been spent on the banks of streams where salmon are in the habit of depositing their spawn, and where of course the parr is likewise abundant. My opportunities of observation have thus been as ample, as my efforts have been unremitting and laborious, to discover the true history of this invaluable species. I shall here present a brief abstract of my earlier proceedings in relation to the subject.

The ammonites dealt with in this paper belong to the family Echioceratidæ (Buckman, T.A., 1913), a varied group of slender, generally evolute forms, usually ornamented by ribs but very rarely tuberculate. In many members of the family the periphery has only a feeble keel, but in some a sharp keel, with or without sulci, may be present.

Ammonites of this family have most frequently been recorded as Ammonites raricostatus, and the raricostate species are by far the best known. The species at present classified with the Echioceratidæ, however, can be roughly grouped, with reference to their form only, as follows :—

1. Raricostate forms, with strong widely spaced ribs and feeble carina, e.g. A. raricostatoides, A. zieteni.

2. Forms with closely spaced ribs, with carina absent or feeble, e.g. A. viticola, A. prorsum.

3. Forms with elevated whorls, bearing regular ribs of moderate strength and with carina and sulci, e.g. A. aplanatum.

4. Forms becoming smooth on the last whorls, which are thin, with an acute keel and obsolescent sulci, e.g. A. macdonnellii.

Dear Sir,

Having, as you know, bestowed a good deal of time and attention on the study of that part of physical astronomy which relates to the mutual disturbances of the planets, I have, naturally, been led to consider the various methods of resolving the formula (a2 + b2 − 2ab cos θ)2 into infinite series of the form A + B cos θ + C cos 2θ + &c. In the course of these investigations, a series for the rectification of the ellipsis occurred to me, remarkable for its simplicity, as well as its rapid convergency. As I believe it to be new, I send it you, inclosed, together with some remarks on the evolution of the formula just mentioned, which, if you think proper, you may submit to the consideration of the Royal Society.

The occurrence of Monograptus in the Carmichael Burn section of the Midland Valley of Scotland has now been confirmed. A new fauna is described from beds previously regarded as Ludlovian which are here suggested to be of Valentian age. A detailed stratigraphical succession has been established and the structure of the area revised in the light of this new information, most of which was derived from a number of exploratory pits sunk for the purpose. Tentative correlations with the other Midland Valley inliers are attempted and many problems requiring future solution are raised.

Sparassodonta is a diverse group of extinct metatherian predators that include forms with diets ranging from omnivores to hypercarnivores, including potential bone-crushers and sabre-tooth specialised species. Most of the previous dietary studies on the group were based on qualitative approaches or dental morphometric indexes and/or bite force estimations. In this study, we explore the evolution of mandible shape and diet of Sparassodonta in a comparative phylogenetic framework, using geometric morphometric tools and allometric and discriminant analyses. We analysed the mandible shape of 142 extant species of marsupials and placental carnivores, and 15 fossil sparassodont species. We found that the relationship between shape and size of the mandible is strongly structured by phylogeny, where the more derived borhyaenoids tend to possess stronger and larger mandibles. Derived borhyaenoid sparassodonts and basal borhyaenoids were classified as hypercarnivores (with short and robust mandibular body). Hathliacynid were classified as mesocarnivores or as hypercarnivores, but with lower probabilities and less specialised morphologies (with a long and slender mandible). Although dental morphology suggests that most of the species of Sparassodonta would have been hypercarnivores, the robustness of the mandible seems to be informative regarding the prey size and degree of specialisation. The relationship between mandibular size and shape, and talonid/trigonid relative size, is strongly influenced by the phylogenetic legacy, suggesting that ecological factors could have influenced the evolution of the sparassodonts.