What motto is on the Montresor's coat of arms?In The Cask of Amontillado

When they arrive underground, Fortunato asks about
Montresor's coat of arms and Montresor, the first-person narrator of the story, tells
him it is "A huge human foot d'or, in a field azure; the foot crushes a serpent rampant
whose fangs are inbedded in the heel." Fortunato asks: "And the motto?" Montresor
replies: "Nemo me impune lacessit," which means "No one injures me with impunity." This
may or may not be Montresor's coat of arms and Latin motto. He might be inventing the
whole thing for his secret amusement. After all, he has not been telling Fortunato the
truth since he encountered him in the street. The cask of Amontillado is undoubtedly a
sheer fiction. It is quite possible that Montresor does not have a coat of arms at all.
It is possible that Fortunato suspects Montresor's family is of humble origins and is
only trying to embarrass him, thinking he might force Montresor to confess that his
family doesn't have a coat of arms. The coat of arms that Montresor describes is an
extravagant one--a huge golden human foot crushing a snake with its fangs embedded in
the heel! This may actually be Montresor's coat of arms, but it seems not only fantastic
but too appropriate for the occasion. It almost seems as if Montresor is warning
Fortunato--in Latin!--of what is about to happen to him down there in the underground
vaults.