According to Homer's description of Hermes inventing the lyre - which would become associated with Apollon because Hermes gave it to him to make up for stealing his cattle - there was an animal skin pulled tightly across the open side of the turtle shell that made the body of the instrument.

I'm picturing this, and that sounds like it was closer to being what we know as a banjo. Is there something missing in the history of how the lyre developed? Was "lyre" just "stringed instrument" then?