Arranged in descending order of nitrogen-fixing (acetylene-reducing) potential the sites examined were mesic meadow and peat polygon troughs (equal rank), transition zone between mesic meadow and gravel ridge, gravel ridge, polar dessert, and peat polygon tops. The dominant nitrogen-fixing microorganisms, as in other Arctic areas, were blue-green bacteria, especially those epiphytic on Arctic mosses. The epiphytic association exhibited an optimum temperature for fixation of 20 degrees C. Other bacteria potentially able to fix nitrogen were present in the soils examined but their activity was severely restricted by low soil temperatures and lack of readily utilizable energy sources. These bacteria included members of the genera Klebsiella (the most numerous), Bacillus, Clostridium, and Beijerinckia (scarce). Also present at many of the sites was an unidentified yellow-pigmented fixer which was not Mycobacterium flavum. All fixers were psychotrophic rather than psychrophilic, having an optimum temperature greater than 20 degrees C but capable of slow growth at 5 degrees C or lower. The rate of acetylene reduction by the epiphytic system increased with the number of successive exposures to acetylene, a phenomenon of some significance in any calculations designed to measure the amount of nitrogen fixed in certain ecosystems.

The libraries of British industrial firms are traced from their beginnings in the chemical industry in the last thirty years of the nineteenth century till 1939, by which date they had spread to many branches of industry and had been recognized as an important part of the industrial and library worlds, thus establishing standard patterns of work. The origins and significance of Aslib are discussed.

Bacterial populations of the Devon Island Lowland consist mainly of psychrotrophic aerobes and facultative types, with counts falling within temperate zone limits. Nitrification and sulphate reduction appear restricted but denitrification potential is considerable. Peat polygon and mesic meadow areas have the highest microbial activities, the polar desert the least.

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television corporations, national and international institutes concerned with children's books, schools of librarianship, and publishing companies.Each of these organizations is concerned not only with its own service to children and its policy for its own future development, but also with its place on the national scene and with the implications for national and international standards, cooperation and mutual exchange of ideas and information. There are disparities between library services within a given country and even wider differences between countries, and though individual national characteristics, politics and geography make international uniformity difficult, indeed undesirable, nevertheless within the Section there is progress towards recognition of common principles, pooling of information on commonly workable practices and increasing development of cooperative action in the children's book world. These are the strong features of the Section's functions and activities, and were evident in the lively meetings in Brussels. A list of its officers is provided on p. 259. Another meeting of the Section, open to all, produced an interest and enthusiasm generated partly through a masterly summary of the papers on the theme of library service to minority groups of children, prepared by Walter Scherf, which supplemented the eight papers prepared and available in translation at the meeting, and partly through the ample time given to contributions by many of the participants who added greatly to the information. The written papers were as follows: