Of

the other animals the genera are not extensive. For in them
one species does not comprehend many species; but in one case, as man,
the species is simple, admitting of no differentiation, while other
cases admit of differentiation, but the forms lack particular
designations.

So, for instance, creatures that are qudapedal and unprovided
with wings are blooded without exception, but some of them are
viviparous, and some oviparous. Such as are viviparous are
hair-coated, and such as are oviparous are covered with a kind of
tessellated hard substance; and the tessellated bits of this substance
are, as it were, similar in regard to position to a scale.