in the Soudan, whilst the slave and ox were universally the higher units of value, each particular district had its own distinctive lower unit according to the nature of its products and requirements, so it is most likely that there were many different units of value (but all alike sub-multiples of the cow) in use among the various Greek communities. It is also probable that they must have exercised a certain effect in the formation of the units of silver currency. Nor is evidence wanting for this. I have already maintained (p. 5) that the fact of the occurrence of the type of the cow, or cow’s head, on early Greek coins is evidence that the original monetary unit was the ox. Thus we find the forepart of an ox on the early electrum staters of Samos of the Phoenician standard (217 grs.), which was probably equivalent to a pure gold ox-unit of 130 grs. The bull’s head also appears on the electrum coins of Eretria and of other places in Euboea. But it is with the silver currency that we are now especially concerned. Whilst it was extremely likely that silver coins might in process of time bear the impress of an ox, the general unit of currency, it was still more natural that, as pieces of silver supplanted as units not the ox but its sub-multiples, that is the particular series of articles of barter in use in any particular district, so these silver coins should bear some traces in their types of the ancient units thus supplanted. That eminent scholar Colonel Leake many years ago remarked that the types of Greek coins generally related “to the local mythology and fortunes of the place, with _symbols referring to the principal productions_ or to the protecting numina.” [Illustration: FIG. 31. Coin of Cyrene with Silphium plant.]