The difficulties involved in Aristotle’s list of species in the category of quantity can be made more precise by noting that in several places he seems to commit himself to the view that body is a species in the category of substance (Top. 130b2, DC 2681–3, DA 434b12, Meta. 1079a31, 1069b38). And as I have drawn the genus-species structure in the category of substance above, body is one of the two species immediately under substance. Yet body also appears as a species under the species Continuou