‘O Sea-Poseidon and ye elderly gods’ exclaims the youth in the _Plutus_ when he holds the torch to the wrinkles in the old woman’s withered face. When, in the _Frogs_, Euripides is made to utter what is taken to be a fine old conservative sentiment, Dionysos answers ‘Good by Poseidon, that!’ When in the _Knights_ Nicias the household slave—conservative after the manner of his class—hears that the new demagogue is a black-pudding chandler, he exclaims in horror, ‘A black-pudding chandler, Poseidon what a trade!’ The choice of Poseidon by the conservative party was no mere chance; they believed in him, they swore by him, because they thought they were descended from him. In the case of one noble family, the Butadae, this descent was no mere chance tradition; their family tree was written up in the Erechtheion itself, and they claimed to be descended from a certain Butes, son of Poseidon and brother of Erechtheus. When Pausanias[135] entered the later Erechtheion he saw in the first chamber three altars, ‘one sacred to Poseidon on which sacrifices are offered to Erechtheus in accordance with the command of an oracle, one to the hero Butes, and one to Hephaestos; the paintings on the wall represent the family of the Butadae.’ It is often said that Erechtheus is merely a ‘title’ of Poseidon; this was the view of the lexicographers. Hesychius[136] explains Erechtheus as ‘Poseidon at Athens.’ But the statement about the altar shows that they were _not_ originally the same, the command of an oracle was needed to affiliate them. It is a noticeable point moreover that Poseidon has no temple of his own, only an altar in the ‘dwelling’ (οἴκημα) called the Erechtheion. This sanctuary bearing the kingly name, remains his ‘steadfast house’ and is an eternal remembrance of the days when the king was priest and the god’s vicegerent on earth.