(Πτολεμαῖος), king of EPEIRUS, was the second son of Alexander II., king of Epeirus, and Olympias, and grandson of the great Pyrrhus. Hie succeeded to the throne on the death of his elder brother, Pyrrhus II., but reigned only a very short time, having set out on a military expedition, during the course of which he fell sick and died. (Just. 28.1, 3; Paus. 4.35.3.) The date of lis reign cannot be fixed with certainty, but as he was contemporary with Demetrius II. king of Macedonia, it may be placed between 239-229, B. C.