Abstract
BACTERIA is a generic term that has been applied to an extensive group of single-celled organisms, belonging to the lowest forms of plant life. The bacteria obtain their nutriment from organic matter, either dead or living, and are therefore capable of leading a saprophytic or a parasitic existence. They are amongst the smallest forms of life with which the biologist has to deal, the transverse diameter of the individual cells seldom exceeding a few micro-millimetres, or it may be a fraction of a micro-millimetre. The highest powers of the microscope are consequently necessary for the study of their structure, which is of a simple character, consisting essentially of protoplasm with a containing cellmembrane. The most striking differences are to be found rather in the biological properties of the bacteria as promoters of decomposition, putrefaction and fermentation, or as the originators of morbid processes in plants and animals, than in any distinctive features they possess as vegetable cells. The following account is simply intended to give the reader who is not a specialist a general conception of the main types of these organisms, which form the special study of bacteriology.
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MACFADYEN, A., BARNARD, J. The Form and Size of Bacteria . Nature 63, 9–10 (1900). https://doi.org/10.1038/063009a0
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DOI: https://doi.org/10.1038/063009a0