Moreover, there are in Arabia certain white snakes
with wings which are known as S Y R E N 5i These can
go faster than horses and are even said to fly as well.
Their venom is so fierce that you die before you feel the
pain of the bite.
  'These serpents appeared in Isaiah xiii, 22 (Vulgate).


S E P S is a tiny snake which not only destroys your body
with its poison, but even your bones.' It is the one the
poet (Lucan) mentions, in 'And the corroding Seps,
destroying the bones with the body'.
  'Hence 'septic'.


The Serpent D I P S A is stated to be so small that when
you step on him you do not see him.    His poison also
destroys before it is felt, so that the face of the doomed
man, even when death has already taken place, does not
look sad. Of this one, the poet (Lucan) reports:
    'The Dipsa, trodden upon, twisted back, seized
        and stung the young Ensign
     Aulus, Tyrrhenian by blood. And the pain or the
        feel of the fang-bite
     Scarcely was felt.'