The bloody sword is placed upon their foreheads in token of the danger
and slaughter of that day, and the wiping with the milk is in
remembrance of their nurse. Caius Acilius tells us that, before the
foundation of Rome, the cattle of Romulus and Remus were missing, and
they, after invoking Faunus, ran out to search for them, naked, that
they might not be inconvenienced by sweat; and that this is the reason
that the Luperci ran about naked. As for the dog, one would say that if
the sacrifice is purificatory, it is sacrificed on behalf of those who
use it. The Greeks, in their purificatory rites, sacrifice dogs, and
often make use of what is called Periskylakismos. But if this feast be
in honour of the she-wolf, in gratitude for her suckling and preserving
of Romulus, then it is very natural to sacrifice a dog, for it is an
enemy of wolves; unless, indeed, the beast is put to death to punish it
for hindering the Luperci when they ran their course.

XXII. It is said also that Romulus instituted the service of the sacred
fire of Vestae, and the holy virgins who keep it up, called Vestals.
Others attribute this to Numa, though they say that Romulus was a very
religious prince, and learned in divination, for which purpose he used
to carry the crooked staff called _lituus_, with which to divide the
heavens into spaces for the observation of the flight of birds. This,
which is preserved in the Palatium, was lost when the city was taken by
the Gauls; but afterwards, when the barbarians had been repulsed, it was
found unharmed in a deep bed of ashes, where everything else had been
burned or spoiled. He also enacted some laws, the most arbitrary of
which is that a wife cannot obtain a divorce from her husband, but that
a husband may put away his wife for poisoning her children,
counterfeiting keys, or adultery. If any one put away his wife on other
grounds than these, he enacted that half his property should go to his