Full Idea
In the central books of 'Metaphysics' there are no longer any genera or species. In Z.13 he argues that genera and universals can't be substances. Since genera are not qualities either, they disappear completely from the ontology.
Gist of Idea
In 'Met.' he says genera can't be substances or qualities, so aren't in the ontology
Source
report of Aristotle (Metaphysics [c.324 BCE], Z.13) by Michael Frede - Title, Unity, Authenticity of the 'Categories' V
Book Reference
Frede,Michael: 'Essays in Ancient Philosophy' [University of Minnesota 1987], p.26
A Reaction
Music to my ears. It is so obvious to me that creatures are classified into genera, so genera can't exist separately, that I am bewildered anyone would believe or imply it.
Related Idea
Idea 12351 Genus and species are substances, because only they reveal the primary substance [Aristotle, by Wedin]