What does "amphisbaena" mean?

Amphisbaena: (Zoöl.) A genus of harmless lizards, serpentlike in form, without legs, and with both ends so much alike that they appear to have a head at each, and ability to move either way. See Illustration in Appendix. Note: The Gordius aquaticus, or hairworm, has been called an amphisbæna; but it belongs among the worms.