Narrow, intermittent, fault-bounded outcrops forming the largely Ordovician Highland Border Complex comprise terrigenous-derived turbidities, a dismembered ophiolite, and ophiolite-derived sediments.

New major- and trace-element analyses of the mafic igneous rocks confirm that two main groups exist. One, represented in outcrops the length of the Highland Boundary fault-zone, has a mostly MORB-like chemistry with some trace-element compositions conventionally pointing to genesis above a subduction zone. The other group, found more locally, has an alkalic ‘within-plate’ character. Amphibolites interpreted as ophiolitic ‘sole’ rocks are chemically similar to the MORB-type mafic extrusive rocks. X-ray diffraction of the sedimentary rocks reveals kaolinite to be widespread and this is attributed to tropical weathering of the Highland Border Complex beneath a (?mid-Devonian) unconformity surface. New major- and trace-element analyses show that the turbidities of the Highland Border Complex were derived from a terrigenous terrane similar to that which supplied the Dalradian Supergroup. Inter-lava sediments reflect varied terrigenous (distal turbidites), hydrothermal (iron oxide sediments), mafic extrusive (volcaniclastic silt) and biogenic (jaspers) provenances. The ophiolite-derived Highland Border Complex sediments also have a terrigenous component. Unlike, for example, the early Ordovician rocks of the South Mayo trough (Ireland), coeval differentiated volcanic material is not a significant component of the Complex.

No one existing model adequately explains all the available data. We favour an origin of the Complex in the Ordovician as a small Gulf of California-type marginal basin which was later tectonically emplaced in stages involving a long history of alternating extension, strike-slip and compression.

The existence in Mexico of blight-resistant species of potato has been known for many years, but they occur in the wild and are quite unsuitable for agricultural purposes. In order to utilise their resistance to disease it is necessary to combine disease resistance with the cropping qualities of cultivated forms while eliminating the undesirable characters which are prominent in the wild forms. Breeding work with this object in view has been in progress at the Scottish Plant Breeding Station for several years, and results obtained in the course of testing progenies for reaction to blight infection are discussed in the following pages.

Holocene sea-level changes affected people living in the Pacific Islands and their ancestors along the western Pacific Rim. Sea-level changes, particularly those that were rapid, may have led to profound and enduring societal/lifestyle changes. Examples are given of (1) how a rapid sea-level rise (CRE-3) about 7600 BP could ultimately have led to the earliest significant cross-ocean movements of people from the western Pacific Rim into the islands; (2) how mid to late Holocene sea-level changes gradually created coastal environments on Pacific Islands that were highly attractive to human settlers; (3) a hypothesis that rapid sea-level fall during the ‘AD 1300 Event' brought about widespread disruption to trajectories of cultural evolution throughout the Pacific Islands; and (4) the effects of recent and likely future sea-level rise on Pacific Island peoples.

The early Cambrian Chengjiang biota in Yunnan, southern China has yielded many articulated exoskeletons of the spiny redlichiid trilobite Eoredlichia intermedia, of which some have their appendages exceptionally well preserved. Both of the paired uniramous antennae of a medium-sized holaspis consist of 46–50 short segments (articles), each of which bears a fine spine near its inner edge. Behind the antennae there are twenty-one pairs of biramous limbs: three pairs are situated underneath the cephalon, one pair underneath each of the fifteen thoracic segments, and probably three pairs underneath the small pygidium. The endopod consists of a broad basis and seven podomeres, of which the last is divided into three terminal spines. The exopod is blade-like, and according to one interpretation, is dorsally hinged to the basis of the endopod; an alternative suggestion being that both the endopod and exopod are split from the basis, the latter being independent and not forming part of the endopod. The exopod has a prominent anterior rim, and possesses about forty long filaments along the posterior margin, and short setae along the rounded distal lobe. The basic appendage features of the redlichiid trilobites, and likewise the gut, are comparable to those of other known Cambrian polymerid trilobites that belong to more distantly related clades.

In a recent paper (Gordon, 1938) reasons were given for the belief that semi-arid conditions prevailed during Lower Carboniferous times in the neighbourhood of North Berwick, East Lothian. The evidence was opposed, in a measure, to that advanced by Mr George Barrow in the East Lothian Memoir (1910) to substantiate the same position. He had relied on the absence of fossils as part proof; but, in point of fact, fossil plants have been obtained in abundance from the actual bedded ashes of Oxroad Bay that he considered (a) to be unfossiliferous, and (b) to have been formed in a manner similar to beds on the Springbok Flats of the Transvaal. The plants that have now been obtained showed xerophytic features, and, consequently, a semi-arid climate was proved on positive evidence. Other positive evidence of a lithological character was also presented in confirmation (Gordon, 1938, pp. 352, 353).

This is a study of the functional morphology of the muscular and reproductive systems of the adult beetle, Atomaria ruficornis (Marsham) made by means of serial sections and dissections. An account is given of the skeleto-muscular system of the head, thorax and abdomen with reference to previous work in this sphere. Wherever possible, the muscles described have been homologized with those of other Coleoptera. In a small number of cases, it has been found necessary to use new names for muscles. The probable mode of action of the mouth-parts and foregut during feeding is described. An account is given of the reproductive organs and genitalia of both male and female beetles; the muscular system of the genitalia in both sexes is described fully, and the functioning of the genitalia is discussed.

A batholith of around 10,000 km2 was formed during the Hercynian orogeny in the Spanish Central System (SCS). Geochronological data indicate concentrated magmatic activity during the period 325-284 Ma. This late-orogenic magmatism is essentially granitic with only minor associated basic rocks (< 2% in outcrop). The SCS is a remarkably homogeneous batholith showing a restricted range of geochemical granite types without any evolutionary pattern related to time. These peraluminous granites show a limited variation in Na2O/K2O) (0·60-0·95), K/Rb (140-240), (La/Yb)n (6-13), and Eu/Eu* (0·34-0·62) ratios. This constancy in chemical characteristics is also reflected in their isotopic signatures: most monzogranites have initial 87Sr/86Sr ratios in the range of 0·7073-0·71229, initial εNd values vary between —5·4 and —6·6 and δ 18O values group in the restricted range of 8·9-9·6‰. The lack of significant differences among SCS granitoids, maintained during a long geological period, suggests constancy in the nature of their source regions and conditions of magma generation. (1) Limited range of crustal sources: an essentially magmatic recycling during Hercynian orogen is suggested. Mantle-derived components are very limited and restricted to a minor role in the origin of the batholith. Geochemical and isotopic features of SCS granitoids are compatible with felsic lower crustal sources. (2) Constraints in melt conditions: uniformity in residual mineral assemblages (feldspars and garnet are always present in the granulitic residua) combined with a lack of attainment of equilibrium conditions during accessory phase dissolution in the crustal melting process is suggested. Granitic melts never reach saturation in some trace elements (REE, Th, Y, Zr), restricting their chemical variability. (3) Homogenisation in magma chambers: long-lived magmatic systems whose successive pulses accumulate into large magma chambers have the opportunity to mingle, thus reducing source differences.

The unique specimen of Coccosteus angustus Traquair, from the Lower Devonian Hunsrückschiefer of Germany, is redescribed and referred to Gemuendenaspis n.gen. Previously unrecorded details of its morphology and a reconstruction are given. Its possession of both arctolepid and brachythoracic characters is confirmed and it is suggested that Gemuendenaspis should be referred to the family Gemuendenaspidæ nov., which closely approaches what would be expected in ancestors of the Coccosteidæ.

Isotope ratios of elements such as Sr, Nd, Pb and Hf can be used as tracers of magmatic sources and processes. Analytical capabilities have evolved so that isotope ratios can now be analysed in situ, and isotopic tracers can therefore be used within single minerals to track the changing magmatic environment in which a given mineral grew. This contribution shows that Sr isotope ratios in feldspars that make up plutonic rocks will typically preserve initial isotopic variations, provided precise and accurate age corrections can be applied. Variations in initial isotope ratio can give a core-to-rim record of magmatic evolution and can be used to diagnose open system events such as contamination and magma recharge and mixing.

New single grain Sr isotope data are presented from the Dais Intrusion, Antarctica, which reflect an open system origin for the crystals. The crystal cargo appears to be aggregated and assembled during transport and emplacement. This model, as opposed to a magma body crystallising post emplacement, may be more applicable to plutonic rocks in general, and is testable using the in situ isotopic determination methods described here.

The fauna of the Polar regions is of deep interest to zoologists generally, that of the Antarctic specially so, and in this the Rhizopodist can justly claim his share.

Since the return of the Challenger Expedition in 1876, the later British expeditions to this area, with the exception of the Scottish National Antarctic Expedition, did but little in the way of sounding and trawling in the deeper waters of the Antarctic. Although much additional work has been carried out, and many new and rare species of the higher forms of marine life from this region have been brought to light, comparatively little has been added to the Rhizopod fauna since the results of the Challenger Expedition were published. The following pages on the Foraminifera are due to the energy and enthusiasm of Dr W. S. Bruce, F.R.S.E., and his colleagues. The genera and species here enumerated and described have been obtained from samples of deposits sent to me at intervals by Dr Bruce and Dr J. H. Harvey Pirie, collected by them, during the S.Y. Scotia Expedition in 1903-4, chiefly from the area of the Weddell Sea, where the ocean floor is covered with terrigenous deposits of Blue Mud, or (as Dr Pirie calls them) Glacial Muds and Clays.

The mid-Miocene Aztec Wash pluton is divisible into a relatively homogeneous portion entirely comprising granites (the G zone, or GZ), and an extremely heterogeneous zone (HZ) that includes the products of the mingling, mixing and fractional crystallisation of mafic and felsic magmas. Though far less variable than the HZ, the GZ nonetheless records a dynamic history characterised by cyclic deposition of the solidifying products of the felsic portion of a recharging, open-system magma chamber.

Tilting has exposed a 5-km section through the GZ and adjacent portions of the HZ. A porphyry is interpreted as a remnant of a chilled roof zone that marks the first stage of felsic GZ intrusion. Subsequent recharging by felsic and mafic magma, reflected by repeated cycles of crystal accumulation and melt segregation in the GZ and emplacement of mafic flows in the HZ, rejuvenated and maintained the chamber. Kilometre-scale lobes of mafic HZ material were deposited as prograding tongues into the GZ during periods of increased mafic input. Thus, they are lateral equivalents of the cumulate GZ granites with which they interfinger. Conglomerate-like units comprising rounded, matrix-supported intermediate clasts in cumulate granite are located immediately above the lobes. These ‘conglomerates’ appear to represent debris flows shed from sloping upper surfaces of the lobes. Thus, the GZ can be viewed as comprising distal facies, remote from the site of mafic recharging in the HZ, and the HZ as comprising proximal facies.

Elemental chemistry suggests that the GZ cumulate granites represent a second-stage accumulation from an already evolved melt, and that coarse, more mafic, feldspar+biotite+accessory mineral ± hornblende rocks trapped between mafic sheets in the HZ are the initial cumulates. Fractionated melt accumulated roofward and laterally, and was the direct parent of the ‘evolved’ GZ cumulates. The most highly fractionated, fluid-rich melts accumulated at the roof.

The Criffell pluton in southwestern Scotland (397 Ma, a Newer Granite of late Caledonian age) is concentrically zoned with outer granodiorites of typically I-type aspect passing into inner granite with more evolved characteristics. The zonation is examined in terms of the compositional surfaces of bulk parameters such as SiO2 and Rb/Sr and compositional variation is best modelled as multi-pulse, there being greater variation in bulk composition between pulses than within pulse. Published variations in Sr, Nd and O isotopes reflect the derivation of the pulses from separate and isotopically distinct sources. Other evidence for open-system behaviour includes mingling with mafic magmas to form enclaves, whereas closed-system behaviour is indicated by restite separation in the early granodiorites, and fractional crystallisation in the late granites. A dominant infracrustal I-type magma formed the first pulse followed by magma derived from more evolved crustal rocks (mainly metasediments of varying ages and maturities). Experimental fluid-absent melting of amphibolite and metapelite at about 900°C has shown that significant quantities of melt can be generated, respectively with I-type and S-type characteristics. Despite having similar bulk compositions, these melts have very different viscosities and densities for the same H2O contents (ηS-type>ηI-type and ρS-type≤ρI-type). It is argued that the rheological controls on magma escape from the source region along complex and tortuous pathways favour the more fluid I-type melts over the more viscous (and only slightly less dense) S-type melts. This constraint could have the effect of reversing the expected buoyancy-driven emplacement sequence, and may represent an alternative rheological differentiation mechanism for the formation of some zoned plutons.

The first part of this paper was communicated to the Society on June 1, 1896, and published in the Transactions (vol. xxxviii. part iii., No. 20, pp. 681–755), the data there discussed being mean values of the climatic elements for each day in the year.

In the present paper an attempt will be made to focus the results deduced from an examination and reduction of the various meteorological registers kept in Edinburgh from 1731 to 1736 and from 1764 to the present time, with special reference to secular and other weather changes.

The condensed results of a number of minor papers dealing with subjects which have, in many cases, formed part of the daily routine of observation during the last ten years have also been included. Attention may also be called to the list of remarkable atmospheric occurrences, such as phenomenal gales, snow-storms, auroras, etc., which is contained in the appendix. In presenting this paper my warm thanks must be expressed to Dr Buchan, from whom I received invaluable advice when points of difficulty arose in the reduction of the observations.

Hyalotuff deltaic deposits, a high proportion of volcanogenic sediment and a repeated occurrence of conglomerate with well-rounded clasts constitute evidence for the shallow-water origin of spilitic lavas and volcanogenic sediments in an Ordovician ophiolite at Ballantrae, SW Scotland. One section, >1.5 km thick, shows repeated evidence for a shallow-water origin. This implies accumulation in a subsiding area. In this sense the sequence at Ballantrae is in marked contrast to those found in oceanic islands (hot spots) which are known to grow from deep into shallow water. Neither does it compare well with those from ocean ridges which usually begin in deep water and move, with cessation of vulcanicity, into even deeper water.

The lava sequence at Ballantrae compares well with oceanic island-arc and remnant arc deposits where uplift and subsidence is common. This, the occurrence of intermediate and acidic lavas and clasts, and the restricted palaeontological and radiometric ages support an arc-marginal basin origin for the lavas. Diversity in the chemical composition of the lavas may reflect diverse origins within the marginal basin.

An upward coarsening sedimentary sequence was built by a hyalotuff delta which formed in front of advancing lava flows. As the lavas advanced over the sediments so a sequence was generated where these sediments have a source in lava flows which were eventually to overlie them.

Clasts of tholeiite were derived from lavas which are now spilite. This, together with the presence of spilitic lava clasts and tuff immediately beneath the flow suggests that the spilitisation resulted from metasomatic activity associated with the convective circulation of trapped water, with the lava as a heat source.

The author (1928) of the present communication has already published the results of a field survey of the Lower Old Red Sandstone in Perthshire and Angus, which were linked with those derived by Campbell (1913) from his study of similar and older series of beds in Kincardineshire, to the north-east. For thirty-five miles to the south-west of the R. Tay, no detailed investigation of the sequence or tectonics of the rocks immediately adjacent to the Highland Boundary Fault, separating the Grampians proper from the Central Valley of Scotland, has been undertaken. A comprehensive account of the rocks of this belt in the region around Aberfoyle is available in the paper by Campbell and Jehu (1917).

It is well known that double ovariotomy, when performed prior to puberty, exercises a prejudicial effect not only upon the generative organs but also upon the whole organism. There is, however, some disagreement as to the results of this operation when performed after puberty, and particularly in regard to the occurrence of heat or menstruation.

It is the purpose of this paper to adduce further evidence upon this question, as well as to describe experiments the result of which indicates that the nature of the ovarian influence is chemical rather than nervous.

The late Llandovery (early Silurian) of South China has yielded a locally abundant and diverse microvertebrate fauna. This includes scales of the little-known mongolepids, sinacanthid spines and a whole host of as yet unassigned forms. The material recovered provides a considerable amount of new information about the diversity of fish in the South Yangtze biome during the early Silurian, and suggests that ichthyoliths have a future role to play in Lower Palaeozoic stratigraphic correlation across China and into Mongolia and Siberia. A new family of mongolepids, the Shiqianolepidae, is erected, accommodating the new genus Shiqianolepis with the type species S. hollandi. The description of Shiqianolepis enables the identification of a differentiated squamation in mongolepid fish, a feature which has not previously been recognised. Two further taxa, Rongolepis cosmetica gen. et sp. nov. and Chenolepis asketa gen. et sp. nov., of, as yet, uncertain affinities are also erected.

Most granites result from partial melting within the crust. Granite melts produced at the lowest temperatures of partial melting mainly comprise close to equal amounts of the haplogranite components Qz, Ab and Or, with H2O. Many felsic granites were formed by partial melting under such conditions and are low-temperature types, with crystals of zircon and other restite minerals present in the initial magma. Such magmas evolve in composition, at least initially, through fractionation of that restite. If one of the four haplogranite components either becomes depleted or too low in amount to contribute further to the melt, then melting may proceed to higher temperatures without a contribution from that component. Melting will advance to significantly higher temperatures if there is a critical deficiency in one or more components and a high-temperature granite magma forms, in which zircon is completely soluble. Such magmas are extracted from the source in a completely molten state and may evolve by fractional crystallisation. They are monzonitic, tonalitic or A-type, depending on whether the critical deficiency occurred in the Qz, Or or H2O component. If the Ab component is critically deficient, as in pelitic rocks, the rocks may be infertile for granite production. The control that source rock compositions exert on both the physical and chemical properties of granite magmas provides a unifying element in granite gen

Fifteen specimens of Eristophyton stems from the Lower Carboniferous Cementstone Group of Berwickshire and East Lothian have been examined. Three possess medullary rays comparable to E. waltonii Lacey, the others have rays like E. beinertianum (Göpp.) Zalessky. In one specimen assigned to E. waltonii a leaf-trace subdivides outside the secondary xylem to form an arc of six separate bundles. Another stem of E. waltonii has attached closely spaced petiole bases one of which is clearly identifiable as Lyginorachis with six vascular bundles arranged in an arc. Stems of Eristophyton from five localities occur associated with petioles or rachises possessing a U-shaped vascular bundle with abaxial ridges like L. waltonii Calder. As these may occur mixed with rachises agreeing with L. brownii Calder the latter is regarded as synonymous. Detached petioles found associated with E. beinertianum may possess four or six basal bundles. The evidence suggests that the U-shaped petiolar bundle passes down into four then six basal bundles and such petioles are associated with both E. waltonii and E. beinertianum. Calder (1935, pl. 1, fig. 2) showed dichotomy in the petiole bundle.

In addition different rachises are known possessing a more massive U-shaped bundle but lacking sclerotic nests and sparganum outer cortex. These are assigned to Cladoxylon edromense sp. nov. Cortical nests occur in both E. waltonii and L. waltonii and may be compared with the sclerotic plates in the compressions of Diplotmema dissectum Brongn. and D. patentissimum Ett.. The evidence supports the view that Eristophyton is a pteridosperm with bifurcate fronds known as L. waltonii Calder when petrified and comparable to Diplotmema when compressed.