Who are those (Pontic?) guys?

[Swampster]

So deploying archers in a corner - which would make them more cramped - makes more sense than deploying properly equipped men with swords and shields? Archers around the corner - perhaps so. Massing there and then jumping into the attack - I don't see it.
Meanwhile the shield bearing men are doing what? There is no indication that they escaped en masse.
I'm afraid that it is far more logical in my mind that the shields are dropped before entering the marsh rather than to create a heavily armoured and helmeted sword wielding archer.

I find we are now going round in circles so I shall agree to differ.

[Swampster]

Sekunda's Hellenistic Infantry Reform ... (2001) has photos of a trophy in the BM which has been associated with the Sullan victory at Chaironeia; it has scutum, greaves and Attic-ish helmet which might be Pontic "legionary" equipment - plus a bow. Which probably goes to show that you can't put too much faith in association of weapon types on trophies, or indeed in marshes.

Just in case anyone is interested and doesn't have the book, this is on the BM website http://www.britishmuseum.org/system_pages/beta_collection_introduction/beta_collection_object_details.aspx?objectId=406277&partId=1&searchText=sculpture 2142

[Duncan Head]

That doesn't follow. The whole camp-garrison would have been running away through the marsh, not just the unit of swordsmen who happened to be defending the one corner of the camp mentioned earlier.

But Appian only mentions the one breach in the camp, which implies only the one contingent engaged in melee.

No, it doesn't. It implies only one successful break-in, or perhaps even only one successful break-in dramatic enough to be mentioned. Other Roman contingents were probably attacking other sections of the fortifications, pulling down stakes and trying to cross ditches, and meeting resistance - apparently more successful resistance.
 

The others might indeed have departed via the marshes while this was going on, but would not have left their kit there, particularly their armour(!).

Of course they would! Fugitives are notorious for discarding anything that will hamper their flight. "Some lucky Saian has my shield, I left it hanging in a wood.."; "To save himself from the foe and escape, he cut away his horse's armour, ..."; "and all the heathens were discomfited before them, and they threw away their weapons, and fled".

And no, there is no indication of a controlled retreat by anybody; the impression is given of the entire Pontic army in rout (or at least all the infantry, as I concede the point previously made about the cavalry possibly escaping unattested across the plain).

The sword-armed men would have dropped the bows in the marsh because it is the simplest explanation

It seems to me like a contrived, artificial explanation linking too many unconnected incidents.

And, like Peter, I shall now agree to differ.

[Patrick Waterson]

Finally we are all in agreement. 

Interesting, though, the association of the bow with heavy infantry equipment on the 'Chaeronea' trophy (admittedly including a shield).  I shall leave the matter there.