In a number of naturalist texts, characters are exhorted or exhort themselves to think about the children-the next generation-whether they are born or unborn. Edna Pontellier, an ambivalent mother in Kate Chopin’s The Awakening (1900) is urged by a more maternal character to, “Think of the children; think of them.”1 Although Edna already has two healthy children, in other naturalist-late nineteenth and early twentieth-century writings often marked by interests in determinism, Darwinian theory, and visual and material culture-texts similar warnings are issued to characters contemplating reproduction. For instance, in Jack London’s Martin Eden (1909), Ruth’s mother argues against marrying the lower-class Martin, cautioning that, “Their heritage must be clean.”2 Ruth herself is also afraid, “When I think of you [Martin] and of what you have been.”3 These characters fear not only the social and economic impropriety of a crossclass marriage, but also its uncertain evolutionary effects.