Two species of Tetraconodontinae dispersed in the early Late Miocene from Eurasia into Africa. Tetraconodontinae then became the dominant pigs in the African Late Miocene and Pliocene. Although the dispersal to Africa must have come from SW Asia, no Tetraconodontinae were known from the area dating from the time of this dispersal.

In this paper, a tetraconodontine tooth from the Nuri Yamut locality near AlÇitepe in European Turkey is described. In morphology, size and in geographical and stratigraphical position this tooth is close to a form that is ancestral to part of the African Tetraconodontinae. The tooth is assigned to cf. Conohyus giganteus, one of the species that dispersed to Africa.

The dispersals of these Tetraconodontinae seem to be more or less coeval with that of Hipparion and are assumed to be allowed for by a change in global climate.

So far as regards number of individuals, and their size, this is one of the largest collections of Ascidians brought back in recent years from Antarctic seas. It contains almost exactly the same number of species of Ascidiacea (Ascidiæ Simplices + Ascidiæ Compositæ) as the Discovery collection—viz. fifteen or sixteen—but whereas in the latter collection nearly all the species were represented by single specimens, in the Scotia collection most species can show long series of individuals—in all there are about two hundred specimens, as against the thirty-three brought home by the Discovery.

For the parasites which form the subject of the present communication, I am indebted to my friend Professor Morrison Watson, who found them in a male specimen of Proteles cristatus, Sparrman, of whose myology he has since published an account. Before entering upon a description of the entozoon, it may be allowable to say a word or two with respect to its host, which is not an animal of everyday occurrence. It was first described a little more than a century ago by Sparrman, the Swedish traveller, as occurring in South Africa, where it is known to the farmers as the “grey jackal”; he gave it the name Viverra cristata. The only point in his description of any present interest is that its stomach “ had nothing but ants in it, or to speak more properly, the white termites,” which might be a valuable hint for any one who had the will and opportunity to investigate the life history of the parasite before us.

Ring complex granites of the Peruvian Batholith are tabular bodies with flat roofs emplaced by cauldron subsidence. Marginal precursory ring dykes extend upwards above roof level and a typical intrusion is “H”-shaped in cross-section. Advance of magma by repeated subsidence would give a ladder-shaped profile for such intrusions above the brittle-ductile transition. Close relationships exist between intrusion geometry, emplacement process and petrogenetic evolution. Initially a granodioritic magma chamber lay beneath the present erosion level, trapping a rising mass of dioritic magma. Expansion of granodioritic liquid resulted in the injection of microgranite and tuffisite cone sheets accompanied by roof uplift within a ring fault. Next, during subsidence within the ring fault, liquids from deeper levels in the underlying chamber rose by stoping along the outer margin of the fault to form a ring dyke. Prior to intrusion, this liquid was vertically zoned from rhyodacite downwards to diorite and these liquids became partially mixed during emplacement. Finally, granodioritic magma rose to the present level by subsidence of a roof slab bounded by the ring fault. The precursory ring structures preserve evidence of significant but transient events in the underlying chamber. Liquid differentiation may be significant in the evolution of many large plutons.

A Critical survey is given of the spirit-preserved material of Marsupialia in the Royal Scottish Museum, with special reference to the fœtal stages.

Of the crab-eating opossum, 12 mm., 16 mm., 20 mm., 30 mm. and 70 mm. stage pouch-embryos are discussed in detail, and compared with stages already known for D. marswpialis virginianus. A similar series of Dasyurus quoll, varying from 12·2 mm. to 34 mm., is considered, followed by notes on adults of some of the less well-known Dasyuridæ. Three pouch stages are studied in Peramelidæ and comparison made with data in the literature. In the Phalangeridæ fœtal stages of Pseudocheirus lanuginosus, Schoinobates volans, Trichosurus vulpecula and Acrobates pygmœus are included. Macropodidœ are represented by Macropus robustus stages ranging from 16 mm. (3·4 weeks old) to 138·7 mm.

The Ordovician and Silurian successions between Falahill and Galashiels encompass six flysch-dominated formations: the Upper Ordovician Portpatrick and Shinnel Formations representing the Leadhills Group, the Llandovery Mindork, Garheugh, and Buckholm Formations together comprising the Gala Group, and a formation indeterminate of age within the Hawick Group. Southward ensialic andesitic volcanic arc and northward low- to medium-grade sialic sources contributed sediment, whilst ophiolitic and subduction-related sources made minor contributions. Deposition took place firstly, in a SE-migrating back-arc basin bordering the northerly source, the Laurentian continent. Subsequent NW-directed underthrusting led to formation out of the back-arc basin of an imbricate thrust stack which migrated southeastwards. Ultimately a foreland successor basin formed ahead of the rising thrust stack.

Flysch units are typically associated with linear outcrops of Moffat Shales which are the loci of major steep SE-translating reverse faults, two of which participate in a late-stage sinistral strike–slip duplex with large-scale imbrication. The faults divide the succession into a sequence of tectonostratigraphic blocks, successively younger to the SE. At least six of the ten blocks customarily recognised in the Southern Uplands, Blocks 3–8, are represented, some of which coincide with single or complete formations.

The power of making such a representation of any object, as shall give a distinct idea of its form, is a faculty which artists possess in different degrees of perfection. The principal difficulty is, to get a first delineation of any subject; from this a copy may be made in various ways, with less exertion of talent than was required for the composition of the original.

Various geometrical and optical inventions have been proposed to assist the artist in making an outline of an object which he wishes to represent. The Reticulated Square and other contrivances, for placing every point of the thing to be represented in its proper place in the picture, belong to the first class; the Camera Obscura and the Camera Lucida to the second. When a design is to be copied, a different kind of contrivances will in general be more convenient. It is only of these that I propose to treat here.

Sand waves are well known indicators of a mobile seabed. What do we expect of these features in terms of migration rates and seabed scour? We discuss these effects on seabed structures, both for the Oil and Gas and the Windfarm Industries, and consider how these impact on turbines and buried cables. Two case studies are presented. The first concerns a windfarm with a five-year gap between the planning survey and a subsequent cable route and environmental assessment survey. This revealed large-scale movements of sand waves, with the displacement of an isolated feature of 155 m in five years. Secondly, another windfarm development involved a re-survey, again over a five-year period, but after the turbines had been installed. This showed movements of sand waves of ∼50 m in five years. Observations of the scour effects on the turbines are discussed. Both sites revealed the presence of barchans. Whilst these have been extensively studied on land, there are few examples of how they behave in the marine environment. The two case studies presented show that mass transport is potentially much greater than expected and that this has implications for choosing turbine locations, the effect of scour, and the impact these sediment movements are likely to have on power cables.

The early tetrapod Crassigyrinus scoticus was a large aquatic predator from the mid Carboniferous (late Viséan or early Serpukovian) of Scotland, around 330 My in age. There are five main specimens with cranial remains: an articulated skeleton; two incomplete skulls; and two lower jaws. Crassigyrinus retains several apparently primitive features of the palatal dentition and lower jaw, and its phylogenetic position is disputed. A partial lower jaw resembling that of Crassigyrinus was discovered at Burnmouth in the Borders region of Scotland. The horizon in which it was found is dated as late Tournaisian, CM palynozone, around 350 My in age. Though it lacks dentition, the jaw preserves much of the postsplenial, angular and surangular, whose appearance externally and internally is almost identical to that of C. scoticus. Internally, the jaw shows a similarly limited extent of the suturing between the splenial series and the prearticular, a primitive condition. Externally, the type and distribution of dermal ornamentation closely matches that of C. scoticus, as does the deeply excavated and marginally positioned lateral line groove. As well as external and internal features, all specimens of C. scoticus are of similar skull size, though the Burnmouth jaw is somewhat smaller. If correctly attributable to Crassigyrinus, this specimen extends the existence of the genus by approximately 20 million years towards the base of the Carboniferous.

The glaciation of the South Orkneys is very similar in its general character to that of Graham Land, and it will be convenient, before going on to the detailed description, to give a short summary of already published accounts of the glaciers of that region.

In the following paper ninety-eight rocks collected by Mr F. W. Anderson from the Tertiary lavas and intrusions on the south-eastern margin of the Vatnajökull, and from the Pleistocene and Recent lavas, tuffs and sediments of Kverkfjöll Eystri on the northern margin of the ice-sheet, are described. Interest in the geology of the Vatnajökull region has been revived by several recent expeditions.

The existence of active volcanoes under the Vatnajökull, and the eruptions that occasionally break through the ice-sheet, offer unexampled opportunities for the investigation of the peculiar igneous and sedimentary products which are the results of the contest between ice and volcanism, and for the solution of the “Palagonite Problem”, with which several authors have recently dealt.

The first appearance of dinosaurs during the early Late Triassic coincided with marked faunal changes in terrestrial ecosystems. Most of the major groups of extant tetrapods (or their proximate sister-taxa), including mammaliaforms, crocodyliform archosaurs, lepidosaurs and turtles, also first appeared in the fossil record during the Late Triassic. On the other hand, a number of Palaeozoic ‘holdovers’, such as procolophonid parareptiles, dicynodont therapsids and many groups of temnospondyls, vanished near or at the end of the Triassic. The tempo and mode of this faunal turnover have long been debated, but there has been growing acceptance of a rather sudden event, although the precise dating of such an event remains controversial. However, new discoveries have cast doubt on this assumption. The persistence of non-dinosaurian dinosauromorphs alongside dinosaurs well into Norian times hints at a more protracted turnover. New data on Triassic insect assemblages indicate that turnover among insects may also have been more protracted and possibly not co-incident with the faunal changes among tetrapods. Future work directed toward improved absolute age assessments for major faunal assemblages will be critical for a better understanding of the transition from therapsid-dominated to dinosaur-dominated communities during the early Mesozoic.

§ 1. In a paper published in the present volume of the Transactions of the Society (p. 659, 3rd July 1905), one of the authors of this communication has given a Hydrodynamical Theory of Seiches, and deduced formulae with a view to particular applications. The object of the present paper is to give some account of a series of calculations on which we have been occupied for some time, with a view to work out, a priori, from the Bathymetric Data of the Lake Survey, the Seiche Constants for the three seiches of lowest nodality in Lochs Earn and Treig.

§ 2. As this is the first time that any attempt has been made to solve completely a problem of the kind, we naturally selected lakes having as simple a configuration as possible. A general idea of the shape of the two lakes, and also of the nature of the data from which we have worked, will be obtained from the 3-in. maps reproduced in figures (3) and (4).

The merits of studious men are to be estimated by the aids they have given to the advancement of science, or the literary monuments they have left with posterity; but if the public be gratified by their labours in these respects, readers are generally willing also to be told, who and whence they were.

Three main types of eye have been defined in trilobites; holochroal, schizochroal and the rare abathochroal. At least in holochroal and schizochroal eyes, the lenses consist of oriented calcitic microcrystallites, the so-called trabecula, which run uninterruptedly throughout the lens from top to bottom. It is argued here that these are primary structures and not diagenetic. Holochroal eyes are commonly accepted to correspond to apposition eyes, which are the most common type of compound eyes in arthropods living today. Schizochroal eyes, present only in phacopine trilobites, are characterised by a doublet lens structure, with an aplanatic interface, correcting spherical aberration of the thick lenses to form a sharp focus for incident rays travelling parallel with the optical axis. This classic model seems to be functional for many phacopines. In these the trabecula are present, though all juxtaposed, forming a solid block. In the lenses of some phacopid species, however, the microcrystallites are separated from each other by gaps. If, during life, these gaps were filled with organic material, as the lens grew from the larval stages, or post-ecdysially, each trabeculum would be isolated from its neighbours by an organic sheath. A simple model is proposed here for the generation of the organic sheath surrounding each trabeculum. If the individual trabecula were isolated from each other, then the possibility of a new kind of visual system exists in these ‘derived’ phacopines. The differences between the refractive indexes inside and outside the trabeculum would ensure that each trabeculum acted as a light-guide, so that the whole ‘lens’ becomes a light guide bundle. This would result in a pixelled visual system, unique in the animal realm, but an archetype for modern technology of data transfer.

North of Skye the waters of the Minch conceal Tertiary igneous rocks, probably of great interest, the nature of which may be surmised only from the study of a few small skerries or islands projecting above sea-level. The group of the Shiant Isles is the best known and most interesting of these, and has been described elsewhere; but the more southerly islets, which form the subject of the present communication, are not without importance in themselves, besides forming a useful geological connecting link between the Shiants and Trotternish. As shown in the sketch map (fig. 1), they comprise the little archipelago a league off the Trotternish coast, which will be referred to as the Fladda group; the island of Trodday, two miles north-east of Rudha Hunish in Skye, and three small rocks or skerries lying close to the track of the Harris mail steamer.

Intensive coniferous afforestation of many water supply catchments is taking place in Strathclyde Region. The current concern over the impact of this significant change in land use on the quantity and quality of water supplies is discussed. Some effects, such as high sediment run-off associated with ploughing and road development, may be of dramatic short-term effect, while others, such as reduction in quantitative yield, the development of eutrophication or acidification with aluminium leaching from soils, may take longer to materialise. Selective routine water quality monitoring work commenced in 1984 in a number of water supply catchments aimed at identifying forestry-related water quality trends. The initial results of this work are presented. Against the background of catchment land use changes, new European Community water supply standards were imposed in 1985 committing the Region to a substantial capital expenditure programme over a ten-year period in order to upgrade water treatment works. Any significant long-term changes in water quality associated with forestry activity will make this programme more costly to achieve. It is considered that the water supplies most susceptible to forestry related quantity or quality problems are the small supplies in areas of Argyll, Ayrshire and the Islands. It is suggested that the way forward is for improved advance consultation and planning on a site specific basis to protect public water supply interests.

The structure of the eye in Isopods has been less studied than in any other group of Arthropods; the only modern descriptions of the minute anatomy of the eye in these crustaceans known to me are by Grenacher of Porcellio, by Bullar of Cymothoa, by Bellonci of Sphæroma, by myself of the genus Serolis. I have lately had the opportunity, while engaged upon my Report upon the “Challenger” Isopoda, of investigating the eye in several species of Æga and allied genera. The structure of the eye in these Isopods differs very materially from the descriptions given by Grenacher and Bullar, but agrees very closely with the structure of the eye in Serolis.

Of all the localities that have yielded a diversity of Carboniferous tetrapods, the fossil assemblage at East Kirkton most closely resembles that of the Joggins locality in Nova Scotia. Both assemblages are dominated by dendrerpetontid temnospondyls and a smaller number of small anthracosaurs, which are thought to have been primarily terrestrial in habits. Both localities lack adelogyrinids and lysorophids, and such presumably deep water genera as Crassigyrinusand large embolomeres. The East Kirkton Limestone differs in the presence of aïstopods and a possible nectridean, which are associated with a shallow-water environment in other localities. The absence of amniotes and microsaurs may be explained by the later evolution of these groups, their limited geographical distribution, or the lack of any aspects of the depositional environment that would preferentially select primarily terrestrial animals.