Her face and torso of a beautiful woman was depicted as winged in archaic vase-paintings, but always with the body of a serpent. She is also sometimes described as having two serpent's tails.

the goddess fierce Echidna who is half a nymph with glancing eyes and fair cheeks, and half again a huge snake, great and awful, with speckled skin, eating raw flesh beneath the secret parts of the holy earth. And there she has a cave deep down under a hollow rock far from the deathless gods and mortal men. There, then, did the gods appoint her a glorious house to dwell in: and she keeps guard in Arima beneath the earth, grim Echidna, a nymph who dies not nor grows old all her days. (Theogony, 295-305)

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