The maritime part of Mygdonia formed a district called Amphaxitis, a distinction which first occurs in Polybius, who divides all the great plain at the head of the Thermaic gulf into Amphaxitis and Bottiaea, and which is found three centuries later in Ptolemy.
The whole group settled at Delphi but soon came to be unable to sustain themselves so they proceeded to move first to Iapygia in Italy and then to Bottiaea in Thrace.