250 ON THE REPRESENTATION OF surface was overlaid in order to receive the colouring, or perhaps to the colours them selves The lighter the mask the more convenient it would be for the performer, and though the description in Lucretius seems to be inconsistent with Millin's conjecture that it was made of cork^, there is no reason why it should not have been moulded from the bark of some other tree^ moistened in water, and then modelled in a bust. The oscilla, or heads of Bacchus, which were imitations of the tragic mask, and which were sus- pended from the pine-trees near a vineyard*, in order that the district might become fruitful, whereon the face of the god was directed by the wind^, were most probably made of bronze or copper ; for the lighter substance would not have stood the effects of the weather. One of the oscilla preserved in the British Museum is of marble, and has a ring on the top for the purpose of suspension. The masks in the Pio-Clementine Mosaic are mostly of a swarthy colour; those in the Cyrenaic picture are quite natural ; and it is probable that a resemblance to nature was 1 As in Petronius : Dum sumit creteam faciem Sestoria, cretam Perdidit ilia simul, perdidit et faciem. '^ Descr. cVun Mos. p. 6. '^ Virgil, Georg. ii. 387: Oraque corticibus sumunt horreuda cavatis. •* Id. ibid. 389 : Oscilla ex alta suspendunt moUia pinu. ^ Id. ibid. 390: Hinc omnis largo pubescit vinea fetu Complentur vallesque cavse saltusque profundi, Et quocunque Deus circum caput egit honestum. Creuzer supposes {Symbol, iv. 93) that this practice referred to the purifying influence of the wind, indicated by the worship of Bacchus Lichnites.
