This article explores the sudden spate of stories concerning the so-called “blue gum negro” (the Blue Gum) that circulated in the national press from the late 1880s to the late 1890s. These reports concerned purportedly blue-gummed, Black assailants, whose bite was alleged to be poisonous, and of whom African Americans were supposedly terrified. This article argues that, although these narratives reinforced white notions of Black criminality and credulity, they marked a particular moment of racialization, in which fears of bodily contagion, generated by the recent revolution in germ theory, were harnessed to notions of embodied racial difference, to express and galvanize white anxieties about racial impurity. Because Blue Gums embodied dysgenic menace, white journalists and writers were often reluctant to disavow their existence, instead capitalizing on the slippage between figurative and literal language that characterized discourse on race. However, in appropriating Black culture and presenting a figure from folklore as a racial type, white writers betrayed not only the essentially superstitious character of racial thought but also the interwoven nature of dominant and subjugated cultures in the United States.