As many cultural historians of the sciences have recently indicated, eighteenth-century illustrations of natural historical works represent an important source that can be used to explore the ways in which nature and the study of nature were regarded in the period. Naturalistic illustrations, however, are not the only genre of images that may help the historian in this investigation. Another interesting source is represented by images of nature and natural objects connected with fictional literature. Yet, little attention has been devoted (...) so far to this genre of images. In this paper I analyse some of the engravings which illustrate Retif de la Bretonne's imaginary voyage La Decouverte australe par un homme volant. My aim is to show that these illustrations convey a well-defined image of the natural universe, and that their analysis may contribute to our understanding of the various significances and roles attached to Nature in the period-particularly bringing to the fore its moral and political uses. Further, by analysing the ways in which they connect and integrate a variety of artistic and discursive traditions related to fiction, travel, and natural history, I hope to suggest some of the ways in which this genre of images may be used to shed light on the eighteenth-century interplay between spheres of knowledge later assigned to such distinct disciplines as 'science', 'literature', or 'art'. (shrink)