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.

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 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.

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 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.

The writer recently undertook an investigation of certain aspects of the water relationships in the gametophyte of Polytrichum (2), showing that a large quantity of water ascends through the central strand of the stem and is given off in transpiration from the leafy shoot. The experiments were later extended to the sporophyte, the transpiration rate again being measured (3). While these observations were in progress, it was suggested that it would be useful at the same time to examine in detail the structure of the absorbing organ of the sporophyte, usually referred to as the “foot,” an organ which has been defined by Hy (16) as that part of the seta which is embedded throughout its life in the tissues of the gametophyte.

The problems of regeneration, and those relating to the production of adventitious structures in general, have not been extensively studied in the Lycopodiales, although the production of adventitious structures, some of them regenerative in nature, has been recorded for all four of the living genera. Selaginella has been examined more thoroughly in this respect than the other three genera. Adventitious roots have been induced to develop from decapitated rhizophores and from isolated lengths of stem; the production of adventitious shoots from rhizophore rudiments has also been obtained by experimental methods. Goebel (7, p. 1220) has described the development of adventitious buds on the leaf bases of Isoetes lacustris, and Osborn (12) has described interesting regenerative developments from detached leaves of Phylloglossum Drummondii. A number of examples of regeneration in various species of Lycopodium has been recorded. Goebel (5, p. 46) states that the first leaves of embryo plants of L. inundatum may produce adventitious shoots. The same writer (6, p. 83) has recorded, but not described in detail, the development of adventitious outgrowths from the decapitated shoots of young plants of L. Selago and from isolated bulbil leaves of the same species. The development of adventitious buds on isolated roots and leaves of L. ramulosum has been described by Holloway (8).

Systematists agree that the Asteropid Ostracods are closely related to the other subfamilies of the Cypridinidæ. Asterope agrees with Cypridina in the form of its antennules and antennæ, in the peculiar bottle-brush second trunk limb so characteristic of the Cypridinidæ, and, to a lesser extent, in the gnathobasic armature of its mandibles, and yet, in its mouth parts, especially the maxillules and maxillæ, Asterope differs totally from Cypridina, and, in fact, from any other Crustacean. Attempts to homologize these limbs with those of other Ostracoda have been made by many systematists, but without much success. Thus recently Skogsberg (1920, p. 39), referring to the maxillule of Asterope, states: “This far-reaching modification and the total lack of known transitional forms makes any attempt at homologization merely a caprice, at worst obviously incorrect, at best unverifiable”; and Hansen (1925, p. 69), discussing the maxillule, states that “the chitinization is weak and lobes rudimentary that it may be impossible to interpret all points with real certainty before forms intermediate between Cypridina and Asterope have been discovered—if they exist.” Despite this impasse along purely morphological lines, I think it is possible, by studying the feeding mechanisms, to establish the relationship between the Asteropid and Cypridinid constitution.

In the course of researches on the reproductive system of Cavia attention was drawn to certain variations in the rapidity of the repair of the endometrium after parturition. It was shown by Loeb (1914) and by Stockard and Papanicolaou (1917) that in the guinea-pig there is a close correlation during the œstrous cycle between the changes in the uterus and the events in the ovaries. It happens that in practically all the animals used for embryological researches in this department the ovaries were preserved and have been serially sectioned. It seemed worth while, therefore, to work out in the material available the relations of the post-partum changes in the uterus with the conditions in the ovaries. Recent researches have brought to light further interesting correlations between the anterior pituitary and the ovaries, and indirectly with the uterus, but in the present communication no attempt will be made to deal with this larger question.

The first part (5) of a study of the quantitative distribution of the bottom-fauna in Scottish waters, and of the natural faunistic divisions of the North Sea and adjacent areas, dealt with the distribution of the molluscs in the North Sea. In this paper the echinoderms from the same area are treated on similar lines. In addition the natural faunistic divisions, as shown by the distribution of the dominant species of molluscs and echinoderms, and the validity of Petersen's community concept as applied to the North Sea, are discussed.

Reference should be made to the earlier paper for information concerning the methods of collecting, the area covered by the Scottish surveys, similar surveys carried out by other workers in the remaining parts of the North Sea, the number of hauls in each square, and other introductory matters.

In 1925 Professor A. E. Trueman handed to the writer a copy of Professor Bertrand's paper, “Les Zones Végétales du Terrain Houiller du Nord de la France” (1914, p. 208), with the suggestion that it would be interesting to find out whether the succession of plants in South Wales is similar to that of the North of France, and to determine whether Bertrand's zones can be applied to the Coal Measures of South Wales. Since that time every opportunity has been taken to collect fossil plants from known horizons in South Wales and other coalfields. In addition, specimens have been examined in all the important museums and private collections, and in particular in the collections of the late Dr R. Kidston, which are now preserved in the Museum of Practical Geology.

The term “Hebrides” is of unknown origin. Some authorities suggest that it meant “the islands of Brude,” called after the names of several Pictish kings. There seems also to be considerable uncertainty about the name “Lewis.” Some derive it from “Leog,” a marsh. Macculloch traced it to “Loda,” a Scandinavian deity. The name has appeared in various forms, the earliest of which appears to be “Leodus.” Another suggestion is that it may be after “Leutha,” the last of the three Pictish kings who ruled in Orkney (Mackenzie, 1903, pp. xxxvi-xxxviii).