There is also a difference in structure in the gut of the two
groups of animals above mentioned (those with unsymmetrical and
those with symmetrical dentition) in size, in thickness, and in
foldings.

The intestines in those animals whose jaws are unequally
furnished with teeth are in all cases the larger, for the animals
themselves are larger than those in the other category; for very few
of them are small, and no single one of the horned animals is very
small. And some possess appendages (or caeca) to the gut, but no
animal that has not incisors in both jaws has a straight gut.