Chapter 21
Genus and property have this in common, namely: that they both follow the species, that is to say, are predicated of them; that they are both predicated equally of the things of which they are predicated; and that they are predicated univocally. The differences between genus and property are: that the genus is prior by nature to the property; that the genus is predicated of several species, whereas the property is predicated of one; that the property is convertible with the species, but the genus never; and that the property exists in just one species, while the genus does not.
See alternate