In the sixth century the stele is commonly adorned with a portrait of the deceased in low relief; but sometimes a painted portrait takes the place of one in relief. Not all stelae, however, were of tall and narrow form, nor was the device on them always limited to a single figure: groups sometimes make their appearance, and to accommodate them the stele has to be made broader. This development we will trace in the next period. Meantime we must say a few words as to the pillar (κίων) which is frequently mentioned as well as the stele in ancient epigrams. The small round pillar, carved with a simple inscription, which is so abundant at Athens, belongs to the later age of the city. But in early times pillars were frequently set up on graves, and surmounted with a portrait or figure of some kind. As examples we may cite the supposed grave of Orpheus in Pieria, which was marked, according to Pausanias[117], by a pillar surmounted by a hydria; and the grave attributed to the sons of Oedipus, Eteocles and Polynices, on which stood a pillar supporting a shield[118]. On the grave of Aristomenes at Messene also was a pillar to which the ox, annually destined to be sacrificed to the hero, was tied[119]. At a later time the grave of Epaminondas was marked, like that of the sons of Oedipus, by a pillar supporting a shield, and that of Isocrates by the figure of a siren, standing on a pillar 30 cubits high. The oldest existing specimen of a sepulchral pillar is from the tomb of Xenares in Corfu. The terms σῆμα and μνῆμα, which are frequently applied to the tomb both in existing epitaphs and in the epigrams of the _Anthology_, do not seem to refer to any special form of monument, but rather to the purpose of the tomb as a significant monument (σῆμα) or as a memorial (μνῆμα).