The silver guy is a Samnite spearman, according to the book.
Anyway, the formation doesn't really do much for it because the Romans fought in relatively open order:
[quote author=Polybius - Histories, Vol. 2]
Such is the arrangement, general and detailed of the phalanx. It remains now to compare with it the peculiarities and distinctive features of the Roman arms and tactics. Now, a Roman soldier in full armor also requires a space of three square feet. But as their method of fighting admits of individual motion for each man---because he defends his body with a shield, which he moves about to any point from which a blow is coming, and because he uses his sword both for cutting and stabbing---it is evident that each man must have a clear space, and an interval of at least three feet both on flank and rear if he is to do his duty with any effect. The result of this will be that each Roman soldier will face two of the front rank of a phalanx, so that he has to encounter and fight against ten spears, which one man cannot find time even to cut away, when once the two lines are engaged, nor force his way through easily---seeing that the Roman front ranks are not supported by the rear ranks, either by way of adding weight to their charge, or vigor to the use of their swords. Therefore, it may readily be understood that, as I said before, it is impossible to confront a charge of the phalanx, so long as it retains its proper formation and strength.
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