slime mould

noun
  1. any of various simple spore-producing organisms typically found as slimy masses on rotting vegetation, where they engulf food particles by amoeboid movements. Formerly regarded as fungi, they are now classified as protoctists of the phyla Myxomycota (true, or cellular slime moulds) or Acrasiomycota (plasmodial slime moulds)
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Historical Examples of slime mould