It will be observed that the reverse does not in these instances bear the symbols as before, upon an open field, but the field is now enclosed by a wreath. The import of this seems to have been about the same as that of the drawn sword and the sheathed sword in modern heraldic designs. Still other examples will show not only the harmony between obverse and reverse, but how coins were dedicated to more than one divinity. This practice was at first more common in the colonies than in the metropolitan cities. A coin of Crotona of about 479 B.C. has, obverse, eagle perched on the cornice of a temple; reverse, tripod and olive-spray. It would seem likely that this piece was first dedicated to Zeus, and next to Apollo. Zeus often holds the eagle on his hand as falcons were held in the days of hawking, and he is then called the eagle-holder (_exetophoros_). When so represented, the god is commonly seated as at peace; but there is one coin of Messene which shows him holding the bird while he is standing and thundering. Later coins show combinations which are particularly interesting in connection with the symbolism of our own coins. One of the best of these is a Macedonian coin of the time of Perseus--obverse, head of Perseus; reverse, an eagle on a thunderbolt, within a wreath of oak. In connection with this example should be examined a Roman gold coin of about 269 B.C.--obverse, head of Mars; reverse, an eagle holding in its talons a thunderbolt. This type of reverse has been pretty closely copied by designers for our mint. The coins of Athens may have furnished the original for the olive-wreath so common on American coins. They were issued under the auspices of Athene, and bore upon the obverse the head of the goddess. The reverse regularly bore the owl and the olive-bough. These coins were familiarly called owls, just as we speak of eagles in our currency, and just as the English talked of angels and crosses in the time of Elizabeth. Aristophanes jocosely calls the Athenian pieces owls of Laurium, in allusion to the gold mines there, in which they were hatched.