It will be observed that the sphinx of the terra-cotta has human arms. This, and her female sex, bring her into close connexion with other female monsters, who also are winged and have the arms of women, the Harpies and the Sirens. Harpy and Siren are, in fact, not clearly distinguished in art; both are human-headed birds. And both are daemons destructive to human life, since, according to the legends, the Harpies were notable for foul and ravenous habits, the Sirens for a passion for the blood of the sailors whom they drew to them by the sweetness of their singing. As sphinx and Siren were thus both alike the ministers of early or untimely death, it will not greatly surprise us to find that on later monuments Sirens appear in the place of sphinxes. An instance from the museum at Athens is figured (Fig. 47)[143]; the woman-bird is human from head to waist, and is occupied with playing on her lyre. The tomb on which she stood perhaps belonged to some young girl or boy who perished by an untimely death. Yet this is by no means certain. For the Siren of Attic tombs has greatly modified her nature under the kindly influence of Attic poetry and art. She came from the East, almost certainly as a malicious and devouring daemon. But in the ordinary custom of Attic tombs of the fifth and fourth centuries she becomes friendly and sympathetic. Sometimes, as in our example, she plays on a musical instrument. Sometimes she seems to express grief by the movements of her arms, beating her breast, or tearing her hair (see Pl. IV). A passage in the _Helena_[144] of Euripides represents the Sirens quite in the same sympathetic light. Helen, when wailing over the calamities at Troy calls on the Sirens, winged maidens, daughters of the earth, to come and join to her lamentations the music in which they were skilled. [Illustration: FIG. 47. SIREN, FROM TOMB.] The sphinx and the Siren may have originally found their place on tombs as ἀποτρόπαια, stone images of daemons to drive away the real daemons. But they retain their place on the tombs of a more refined age to express sympathy with the mourners, and to add a gentle touch of sorrow to the delightful domestic scenes which usually occupy the front of the monuments. Sophocles calls the Sirens the daughters of Phorcys, who sing the ways of Hades; it cannot therefore seem inappropriate that the tomb of Sophocles himself was adorned with the figure of one of these spirits. [Illustration: FIG. 48. HEAD OF STELE.] More obscure devices are sometimes mingled with the acanthus over the tomb. In a few cases (Fig. 48) we find a pair of goats butting one another over a drinking-cup[145]. The cup seems to show that there must be here some Dionysiac reference or meaning, though what it is we cannot say. In one case a female figure (Fig. 49), the import of which is hard to determine[146], stands over a tomb, with the acanthus-leaves for a background. [Illustration: FIG. 49. HEAD OF STELE.]