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While studying the distribution, within Antarctic regions, of the vascular plants now known from South Georgia, numerous discrepancies were found between the accounts of various authors. The present paper is an attempt to clarify the situation, and has been compiled from the most recent known papers dealing with the flora of each area. Only taxa reported as native have been included in the “Check List” but species reported as aliens have been listed in the section headed “Notes on floras”.

In a recent paper I stated that the hypothesis of a continuously cooling earth had “consistently failed to lead to any adequate explanations of fissure eruptions and other volcanic and tension phenomena, mountain-building processes and their distribution in time and space, and the alternation of marine transgressions and recessions”. It seems to be desirable that I should further justify this sweeping integration of objections, for Dr. Harold Jeffreys, who has actively explored the consequences of this theory during recent years, takes exception to my discouraging view of the position, and claims that the alleged failures include the principal successes of the theory. The evidence on which my summary indictment was based will be reviewed in this paper; and attention will be directed to certain other phenomena—such as the growth of geosynclines—of which the significance has not yet been generally realized. As a preliminary it will be convenient to discuss the gradually converging evidence bearing on the thickness and substructure of the continents.

This paper is concerned with version of Bernstein's inequality for Hausdroff locally compact Abelian groups. The ideas used are suggested by Exercise 12, p. 17 of Katznelson's book [4].

This paper reports the first phase of an extended exercise in benthic ecology, involving both long- and short-term aims. The short-term aim is to examine the benthic fauna of representative substrate types for a period of a year and to compute the net secondary production of the infaunal macrofauna in terms of ash-free dry weight per square metre per annum. The intention is to identify from among the bulk of species those animals which have the highest productive capacity, to rank these in order of productive importance, and finally to give our best estimate of the production of the animal assemblage as a whole.

In an earlier paper (Warwick & Buchanan, 1970) the structure of the nematode communities at three stations off the Northumberland coast was compared. It was shown that the offshore mud community at station ‘C’ was faunistically the most homogenous. This station has been selected for a more intensive investigation of meiofaunal production since it provides the simplest situation for study, and furthermore the type of nematode community found here is thought to be of common occurrence in similar sediments round Northern Britain.

The problems involved in the identification of freeliving marine nematodes have stood in the way of ecologists for some time. Although considerable advances are now being made on the continent (particularly in Kiel Bay and the Mediterranean) and in North America, our lack of knowledge of the British species is still lamentable. In order to rectify this state of affairs to some extent, a study of the distribution of nematodes in the Exe estuary was planned to cover as wide a spectrum of physical and chemical conditions as possible, ranging from fine muds with a low interstitial salinity at the head of the estuary to coarse sands with a high salinity at the mouth. It is hoped that the characterization of the fauna of various habitats in the estuary will form a basis for further ecological studies in other areas. Not surprisingly, a large proportion of the species found were new British records, and some new to science. The fourteen species of this latter group discussed in this paper are described elsewhere (Warwick, 1970).

In previous reconstructions of Gondwanaland the Falkland Islands have been placed in a position intermediate between the Cape Province and Northern Argentina. In the present paper it is suggested on structural, tectonic, and stratigraphical grounds that it would be preferable to position the Falkland Islands due east of the Eastern Province coast, thus completing the truncated Karroo Basin, the missing part of which has until now been suspected to be concealed beneath the ice-capped Queen Maud Land, Antarctica.

In July 1945, the Secretary of State for the Colonies appointed me leader of the Falkland Islands Dependencies Survey for two years, an appointment which brought a prospect of a free existence in the wide open spaces as compared with routine office life. I soon found this prospect fading over the horizon. For months I was tied to an office, early and late, surrounded by scores of papers, insistent questioners and a ceaseless telephone bell. All this was necessary before the stores were ordered, packed and dispatched and the staff appointed.

In Part 1 of this paper a free-streamline wake model mas introduced to treat the fully and partially developed wake flow or cavity flow past an oblique flat plate. This theory is generalized here to investigate the cavity flow past an obstacle of arbitrary profile at an arbitrary cavitation number. Consideration is first given to the cavity flow past a polygonal obstacle whose wetted sides may be concave towards the flow and may also possess some gentle convex corners. The general case of curved walls is then obtained by a limiting process. The analysis in this general case leads to a set of two funnctional equations for which several methods of solutioii are developed and discussed. As a few typictbl examples the analysis is carried out in detail for the specific cases of wedges, two-step wedges, flapped hydrofoils, and inclined circular arc plates. For these cases the present theory is found to be in good agreement with the experimental results available.

Spirula spirula has stimulated considerable interest since it was first discovered. It is a member of one of the two genera of sepioids to frequent oceanic water (the other being Heteroteuthis); it has a unique spiral shell which acts as a buoyancy mechanism and can withstand considerable pressure (Denton, Gilpin-Brown & Howarth, 1967); and, until the capture by the Danish Oceanographical expeditions it was considered very rare, only 12 specimens having been captured. The Dana expeditions caught 193 individuals from 1909 to 1931 and these were described by Kerr (1931) and Bruun (1943,1955). Most of these were caught in the waters around the Canary Islands of the North Atlantic. Bruun (1943) arranged the specimens according to month and size and claimed that two size groups could be distinguished. The specimens were taken over a wide geographical area, in several years and during the months of February (1 specimen), March (40), April (3), May (8), June (1), August (1) and October (23). His conclusion concerning growth depends entirely upon his decision to split the March sample into two year-groups; those above 1.9 cm in ventral mantle length he put in a separate year-class to those below 1.9 cm in ventral mantle length. This division was arbitrary and, one suspects, based on a belief that a one-year life-span was likely. Clearly the growth of Spirula requires further study based on a larger collection and the present paper is an attempt to fulfil this need.

During 1950, the Common Octopus (Octopus vulgaris Lamarck) was to be found along the south coast of England in greater numbers than at any time since Garstang (1900) reported on the ‘plague’ on the coasts of Devon and Cornwall in 1899–1900. In earlier papers (Rees, 1950, 1952) the distribution of the octopus in our northern waters was reviewed, and it was demonstrated that this species is an immigrant which breeds on our south coast only rarely. It reaches these coasts by being brought there as a planktonic larva by the water circulation in the English Channel and by migrations of the adult. The most important factor in controlling the movements of the adult, however, might be expected to be the water temperature in the English Channel—where the species is at the northern limit of its breeding range and might therefore be extremely sensitive to slight changes in temperature.

In this paper we examine the steady, two-dimensional convective motion which occurs in a horizontal circular cylinder whose wall is non-uniformly heated. One observes several qualitatively different physical phenomena depending on the wall temperature distribution and the value of the Rayleigh number. The low-Rayleigh-number behaviour for the single convective cell heated from below is related to the classical Rayleigh stability problem. The critical Rayleigh number for the single circular cell is approximately five times the value for Rayleigh's multi-celluar configuration. The flow which exhibits a nearly parabolic velocity profile near the critical Rayleigh number, gradually changes to a rigidly-rotating-core behaviour as the Rayleigh number increases. The speed of core rotation is a function of the Prandtl number, whereas the boundary-layer thickness is primarily a function of the Rayleigh number. When the heating is from side to side, the solution shows that as the Rayleigh number increases the core motion is progressively arrested leaving a narrow circulating band of fluid adjacent to the wall. An oblique heating produces a hybrid phenomenon, a low-Rayleigh-number behaviour which is characteristic of the sideways heating case and a high-Rayleigh-number interior motion characteristic of the bottom heating case. To determine the core motion in the high-Rayleigh-number limit, Batchelor's work concerning the uniqueness of incompressible, exactly steady, closed streamline flows with small viscosity is extended to include flows with small thermal conductivity.

In this paper a counterpart is given to the data of our investigation about the incidence ofinfantile amaurotic idiocy(Tay-Sachs) in Switzerland, published here in 1954. The term «the-saurismose» is rather unclear and had to be critisised byLetterer. The diagnose of all lipidosis is more difficult than of any other genetic character, as neither a thorough clinical and histological examination nor the chemical analysis of the brain and the big abdominal organs (spleen, liver etc.) is sufficient; it ought always to be completed by the modern histochemical method at least if we want to separate the M. Niemann-Pick from the M. Tay-Sachs. The quarrel between the « unitarists » and the « dualists » concerning the independence of these two phosphatid-lipidosis does not seem to be ended definitely by chemical analysis of the affected organs. Undoubtfully these two very similar diseases must have many common traits in their pathogenesis. This does not mean, however, that they do not depend on 2 different genes, may be working at the same pheno-genetical chain (Klenk), perhaps there is a pseudo-allely, which as a matter of fact can hardly ever become proved in men. This author showed that the M. Niemann-Pick is regularly characterised by a high percentage of sphingomyelin whilst in the M. Tay-Sachs the gangliosids prevail. But recently this difference is regarded to hold only quantitatively. Therefore we have to look for genetical proofs of the independence of these two lipidosis. An observation ofvan Bogaertin his famous pedigree of the family Mi. and another less convincing ofDriessenshow that among the children of the same parents cases of both these lipidosis can appear. Since both these families are of Russian respectively Polish-Jewish origin, coming from a not very big area in which these lipidosis were found relatively very often, thes

This paper describes experiments to determine whether intestinal tissue mast cells and/or intestinal histamine are involved in the second, expulsive step of worm elimination. In neonatal rats, intestinal tissue contains only very little histamine and mature mast cells are encountered only sporadically. From birth to the adult age, there was a gradual rise in both intestinal mast cells and histamine. During Nippostrongylus brasiliensis infection in the adult rat, the concentration of histamine in the small intestine was clearly lower than in uninfected controls.Especially low histamine values were found to occur on days 6-12 of a primary infection in the region where the main worm burden was located. Similarly, the number of tissue mast cells present in the epithelium of the jejunum was decreased in the same region and during the same period of time. From the observation that the bulk of the parasites are expelled at a time when histamme and mast cell levels are low, it was concluded that mast cells and their constituents were not an essential factor in the second step of worm elimination This work was supported by the Schweizerische Nationalfonds zur Förderung der wissenschaftlichen Forschung (Grant 5200.3). The skilful technical assistance of Miss I. Beeger, Miss R. Keist and Miss M. Iseli is gratefully acknowledged. I thank Mr H. Berchtold, Biostatistisches Zentrum der Universität Zürich, for the statistical evaluation of the data

SUMMARYThis paper is based on 45 cases in 27 families, all of which have been studied in Children Hospitals. In Switzerland almost all cases ofinfantile amaurotic idiocy (Tay-Sachs)have probably been collected, so that the stated 13 primary and 14 secondary cases may allow an estimation of the frequency of this character, which seems to oscillate temporarily. In the last 10 years no new cases have been observed.All 24 autochthonus Swiss cases are from non-Jewish, mostly rural origin, in which Eastern Jews are not to be supposed as ascendants.Our in all 27 families with TS make Slome's statistic of Jewish and non-Jewish cases in literature much more significant; the incidence of parental consanguinity is, as a matter of fact, nearly twice as high in families with non-Jewish origin.There is no evidence of a milder and longer course of TS in non-Jewish families.The mode of inheritance is, according to Slome,monohybrid autosomal recessive, though in remarkably many sibships there is an accumulation of cases. The reduction method, however, gives a percentage of 28,3 ± 6,2, coming quite near to the expectation of the Mendelian quarter.The penetrance of the character is total, the expressivity generally very equal, with only a few deviations from the well—known clinical picture of TS.The interfamiliar and intrafamiliar variability therefore is small. In not even one of the families studied have there been found other forms of lipoidosis, principally no cases ofsplenohepatomegalia Niemann-Pick. All available respective cases in Switzerland have been collected by the present author and will soon be published in these Acta. In none of these families with M.Niemann-Pickhave cases of M. Tay-Sachs been seen. This fact is liable to prove that these clinically and anatomically very similar conditions derive from independent i. e. different mutations.Modifying genes may accou