This latter animal,

by the way, resembles certain fishes. For, as
a general rule, fishes have a prickly tongue, not free in its
movements; though there are some fishes that present a smooth
undifferentiated surface where the tongue should be, until you open
their mouths wide and make a close inspection.

Again, oviparous blooded quadrupeds are unprovided with ears, but
possess only the passage for hearing; neither have they breasts, nor a
copulatory organ, nor external testicles, but internal ones only;
neither are they hair coated, but are in all cases covered with
scaly plates. Moreover, they are without exception saw-toothed.