With the renewal of activities in Fishery Research, which took place in the lands bordering the North Sea after the War, fresh lines of investigation were introduced. Amongst others, quantitative surveys of the bottom fauna similar to those carried out by Petersen were undertaken by several countries. The southern part of the North Sea was examined by the Ministry of Agriculture and Fisheries and the results were published by Davis (2, 3). Other work undertaken in the German Bight was published by Hagmeier (6). A small survey was carried out by Petersen (8) in the North Sea off the north-west coast of Denmark. Areas to the north and west of Scotland, as well as the northern half of the North Sea, were surveyed by the Fishery Board for Scotland and a preliminary account published (11). The present paper is, in part, a summary of the results of the survey work carried out by the Fishery Board for Scotland in the northern part of the North Sea during the years 1922-25, supplemented by a subsequent survey of the intertidal areas undertaken privately; in part an analysis of the faunistic divisions of the North Sea based on the distribution of the molluscs, especially lamellibranchs, as recorded in the above papers. So far as the North Sea is concerned, the area covered by the Scottish investigations is bounded on the south approximately by latitude 56° N., and on the east and north by the 200 m. (100 fm.) contour.

The economic importance of the leaf-roll disease of potatoes has been recognised for a number of years owing to the fact that its incidence leads to a heavy reduction in marketable ware. The annual loss to potato growers in England and on the Continent from leaf-roll amounts to a high figure, but the disease is not of such prime importance to the Scottish cultivator as certain other diseases of the virus class to which the potato is prone, namely, mosaic and crinkle.

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 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.

The first known fossil Ostracoda were collected by the Rev. David Ure from the Carboniferous Limestone of East Kilbride. In 1793 he figured his specimens, describing them merely as “microscopic shells.” Some years later Dr S. Hibbert (1836) described and figured as Cypris scotoburdigalensis some Ostracoda he had collected from the Burdiehouse Limestone near Edinburgh. The most important work on this group of fossils was done by T. R. Jones. In 1866, together with J. W. Kirkby, he gave a short account of previous research, and from 1855 until 1901 published a large number of papers, either alone or in collaboration with J. W. Kirkby, H. B. Holl and others, mainly in the Annals and Magazine of Natural History. In 1927 Dr Hopkins used an ostracod bed for correlation purposes in the Northumberland and Durham Coalfield, and in 1931 W. B. Wright observed that the ostracods show a definite succession of forms. A new species described by Wright as Cytherella foveolata occurs at the top of the Pulchra Zone and may be of zonal significance since it has not so far been recognised in any other horizon.

1. During recent years increased attention has been paid to the question of measuring or estimating the extent or degree of disturbance in the earth's magnetic field. Two distinct purposes have been kept in view. The first and more general is to provide some measure of disturbance capable of use as a means of correlating terrestrial magnetic change with other geophysical or cosmical phenomena; in particular, solar phenomena. The second seeks to assign to each Greenwich day a numerical value for the degree of disturbance on that day, so that a selection may be made in each month of a certain number of days on which the terrestrial field has been least or most disturbed. The immediate object here is to secure comparability between results—particularly diurnal inequalities—obtained at different magnetic observatories.

The author recalls the facts regarding the rediscovery, in recent years, of Carter's genus Conulites ( = Dictyoconoides Nuttall). He shows how, of seven species which have been referred to this genus, three always have numerous intercalary whorls in their spires, and four never have any such whorls. The association of these two groups together within a single genus has, so far as he himself is concerned, been due to the uncertainty hitherto existing regarding the type species cooki, whose spire was stated by Carter sometimes to show an intercalary whorl, but generally to be “single throughout.” Carter's original specimens, which had long been mislaid, have recently been found, however, and they all prove to belong to now familiar types, which invariably contain numerous intercalary whorls in their spires. The author therefore separates the four species which do not possess such whorls into a new genus, Lockhartia.

The author next discusses the supposed identity of Dictyoconoides with Rotalia, and shows that the Rotalia must be judged by their type species R. trochidiformis. He shows that this species, among other characteristic features, invariably displays the structures called “astral lobes” by Carpenter and Brady, and is distinguished by the same from both Dictyoconoides and Lockhartia; while it is further distinguished from Dictyoconoides by the absence of intercalary whorls in its spire.

The author then compares the development of Rotalid forms, like the above, with that of piano-spiral ones like Nummulites and Assilines; and he finally shows the fundamental difference in structure between all these spirally wound types and those with an “end-on” development, like the Dictyoconus group of forms, with which some of them have been confused in the past.

Since 1860, in which year De Bary published his great work Die Mycetozoen, the investigation of the life-history of members of the Mycetozoa has aroused a considerable amount of interest, and a great deal of important research has been carried out in this connection. The group of organisms is particularly interesting, because it lies on the borderline between plant and animal kingdoms, and it is very possible that a detailed investigation of several species of the Mycetozoa might be of considerable assistance in elucidating certain obscure points in the life-histories of higher members of both the great natural groups. The term “Mycetozoa,” which we owe to De Bary, will be used throughout in preference to the older term “Myxogastres” invented by Fries (32, p. 2), and that of “Myxomycetes” first employed by Link (32, p. 2). “Mycetozoon,” or “fungus-like animal,” is a very appropriate description of a member of the group, since during part of its life-history it exhibits distinctly animal-like characters, and the individuals move rapidly by means of flagella, whilst later, during the development of the sporangium, a plant-like form is assumed. The combination of plant and animal characters has given rise to much discussion as to the position of the Mycetozoa in plant or animal kingdom, and the group has been claimed by both zoologists and botanists.

The purpose of this communication is to describe, and to discuss the significance of, (1) the extensive morainic deposits and the associated glacial phenomena of the tract of country situated immediately west of the Ochil Hills (border of Perthshire and Fifeshire)—between the River Teith near Doune, north of Stirling, and the River Tay in the vicinity of Perth; and (2) a well-marked later glaciation studied in the region of Loch Lomond and the Upper Forth valley.

In both instances these glaciations involved readvances of the ice during the retreat of the last general ice-sheet, and for brevity and convenience of description they will be referred to as the Perth Readvance and the Loch Lomond Readvance.

At the end of 1926 a paper by Dr Maclaren entitled “Development of Cavia: Implantation” was published in the Transactions of the Royal Society of Edinburgh (2). In this he dealt with the process of implantation of the blastocyst, and incidentally gave a tentative interpretation of the nature of the layers of which it was formed. The paper was to have been followed by a further contribution dealing especially with the earlier stages in the history of the blastocyst. This was held up for various reasons, and was not ready for publication until 1930, when there appeared appaperd on the subject by Professor Hill and Dr Sansom (6). This forestalled to a considerable extent Dr Maclaren's demonstration of the facts of observation, but there remained to him more than a dozen examples of free blasto-cysts at younger stages of development than the earliest figured in their paper, and indeed of any other worker on the development of Cavia. He then thought that it might be more interesting and instructive if the fixed and sectioned material were controlled by observations on the living blastocyst. A technique for this was developed, and apparatus designed by which living blastocysts could be observed and photographed. Eminently successful in the case of mammals with large blastocysts and tardy implantation, the results obtained in Cavia were disappointing owing to the excessive minuteness of the blastocyst, and to its being very early involved in one of the crypt-like recesses in the mucosa.

Although it is unlikely that the east of Sutherland will ever rival the west in geological renown, its varied interests have already furnished material for a considerable literature. Attention has been specially focussed upon a down-faulted coastal strip of Mesozoic rocks, which, starting at Golspie, extends north-eastwards for twenty miles through Brora and Helmsdale to the county boundary at the Ord (fig. 1). Golspie itself stands on a narrow outcrop of Trias. Jurassic follows, with a generally ascending sequence that leads up to Kimmeridgian at Kintradwell, a couple of miles north of Brora (fig. 2). Beyond this Corallian reappears, but only for a short distance. Then Kimmeridgian returns and holds the coast-line continuously for nearly nine miles, until, at the Ord, it disappears beneath the sea. The width of the Kimmeridgian exposures is occasionally three-quarters of a mile, but generally much less.

The paper which follows is based in the main on the magnetic records of the observatories at Lerwick (Shetland) and Eskdalemuir (Dumfriesshire), though reference is made to the data of Abinger (Surrey), Sitka (Alaska), Sodankylä (Finland), Colaba (Bombay), and Mauritius, and to records made at different times at Arctic and Antarctic stations. The situation of the Lerwick observatory, just within the auroral zone, might be expected to give to its records an outstanding value in any investigation connected with magnetic storms; the expectation has not been disappointed. The distance between Abinger and Eskdalemuir is about 470 km., and between Eskdalemuir and Lerwick about 550 km.—both quantities small compared with the dimensions of the earth—yet the mean ranges of disturbance at these three places appear to run roughly in the ratio 1:2: 4½. This at once suggests that in the extreme north of the British Isles we approach a zone of exceptional interest from the point of view of magnetic disturbance; and further,-that with suitable magnetic data some attempt might be made to compute the disturbing electric fields, at least in their main features, and possibly to arrive at some idea of any seasonal and annual changes to which these fields may be subject.

The remarkable and close parallelism exhibited by the suctorial disc of the fish Garra and of certain tadpoles belonging to frogs of the section Rana formosa of Rana was pointed out by the late Dr Annandale and myself in 1922. Evidence was then adduced to show that such structures have come into existence through a gradual accumulation of small changes, which probably originated in direct response to the increasing swiftness of the currents as the animals invaded higher and higher levels of torrential streams. The probable evolution and the development of the disc of Garra have been described already (Hora, 1921, pp. 639–643); whereas the peculiar structure of the disc in the tadpoles has hitherto been known only in its fully-formed condition. It seemed probable that, with the discovery of the earlier stages in the development of the disc, the line of evolution of the sucker would prove to be similar to that of the sucking disc of the fishes of the genus Garra (Hora, 1930, p. 241). The observations described hereafter confirm this view.

It is a familiar experience for the teacher in charge of a class dissecting Rana temporaria to notice or have his attention directed to blood-vessels in an abnormal position or absent from the place where they were expected. Sometimes, perhaps too frequently, they are ignored; but they are of interest, not only in themselves, but also because they throw light on problems that have arisen in other lines of work. From time to time such abnormalities have been reported in R. temporaria and in other Anura, but the literature of the subject is scattered in different journals.

Whilst the specimens of Bothrodendron mundum Williamson sp. in the Kidston Collection of fossil plant slides in the Glasgow University Botany Department were being examined, certain structural characters were observed which have not been mentioned in previous descriptions of this species. These characters appear to be of sufficient importance to justify the present description, and at the same time it may be noted that photographic illustrations of the aerial stem of this species have not, so far as is known, been previously published.

The arrangement of the structures subserving the phenomena of the heart-beat has long been the study of anatomists and morphologists. Current descriptions are incomplete in essential particulars, and much confusion and uncertainty has arisen from the well-known fact that apparently the structures which conduct the impulses initiating muscular contraction in other parts of the body are duplicated or supported, in the heart, by a specialised mechanism. This mechanism is said to consist of atypical muscular fibres, accompanied by nerves, and arranged in anatomically distinct portions, nodal and bundle. In the nodal portions of the mechanism the fibres are smaller than those of the myocardium, and form a close entanglement, probably syncytial; while in the bundle of His the fibres vary in size in different animals. Ventricular extensions, again of widely divergent types, are well known under the name of Purkinje fibres. While two nodal portions are described, one, the sino-atrial node, at the commencement of the venous portion of the heart, the other, the atrio-ventricular node, at the end of it, only one distinctive pathway establishing continuity throughout the special mechanism has been demonstrated, namely, the atrioventricular bundle of His. Subsidiary structures of a like kind have been demonstrated, for example Kent's accessory atrio-ventricular bundle, but “no distinctive pathway between the sino-atrial and atrio-ventricular nodes has yet been demonstrated,” although the results of experiment have indicated the probable existence of such a communication (9).

The Stor Fjord is the great bight which is situated on the eastern side of the mainland of Spitsbergen, and separates it from the large Barents and Edge Islands which lie farther east (see map, fig. 1). It is widest towards the south, the distance between the South Cape of Spitsbergen and Negro Point on Edge Island being 107 miles. At its northern end the Stor Fjord narrows considerably and terminates in Heley (or Helis) Sound, which connects it with the Barents Sea by way of Olga Strait.

Our knowledge of the nature and mode of action of the nervous mechanism of the uterus is far from complete. The following paper is a continuation of that published by the Royal Society of Edinburgh in 1927 (38).

In that paper a short historical summary of the previous work was given. To expand this summary and fully analyse the further papers I have studied on the special points of my present communication would unduly lengthen this memoir. I will therefore confine myself to a brief abstract of my former results, and a short statement as to the present state of our knowledge. A full bibliography will be found at the close of this communication.

It is well known that there are two distinct horizons in the Caledonian Lower Old Red Sandstone which contain abundant plant-remains (Evans, 1929). At the lower horizon of the Carmyllie and Cairnconnan Beds the flora consists, so far as is clearly known, of Pachytheca, Nematophyton, Parka, and one vascular plant, Zosterophyllum myretonianum (Lang, 1927). In certain greenish-grey flags and sandstones of the Strathmore Beds near the summit of the stratigraphical succession fragmentary plant-remains are abundant along a line stretching from Rosemount, south of Blairgowrie, through Murthly, Glenalmond, Callander, and Balloch, to near Brodick in Arran. From these beds a small but quite distinct assemblage of fossil plants is known. Pachytheca is clearly recorded. The well-defined remains of vascular plants have so far all been referred to Arthrostigma gracile, Dawson, and Psilophyton princeps, Dawson. References to Psilophyton robustius occur, but there is no evidence that the type of plant distinguished from Gaspé under that name has been found in the Strathmore Beds.

The coast of Northern Trotternish has long attracted the attention of geologists for two reasons, the first being the intermittent exposures of highly fossiliferous Jurassic strata preserved below the great Tertiary lava plateau; and the second, the striking columnar sills of igneous rock which have been intruded into these Mesozoic beds. Intrusive phenomena unparalleled in Britain may be observed (preferably from the sea) from Holm to Staffin Bay, and in slightly less perfect form round the Aird to Duntulm and Camas Mòr.