If the question be raised, ‘why did the Greeks image the dead hero as a snake?’ no very certain or satisfactory answer can be offered. Aelian[854] in his treatise on ‘The Nature of Animals’ says that the backbone of a dead man when the marrow has decayed turns into a snake. The chance, sudden apparition of a snake near a dead body may have started the notion. Plutarch[855] tells how, when the body of Cleomenes was impaled, the people, seeing a great snake wind itself about his head, knew that he was ‘more than mortal’ (κρείττονος). Of course, by the time of Cleomenes, the snake was well established as the vehicle of a hero, but some such coincidence may very early have given rise to this association of ideas. Plutarch adds that ‘the men of old time associated the snake most of all beasts with heroes.’ They did this because, he says, philosophers had observed that ‘when part of the moisture of the marrow is evaporated and it becomes of a thicker consistency it produces serpents.’ The snake was not the only vehicle. As has already been noted (p. 305), the spirit of the dead could take shape as a human-headed bird or even perhaps, if a bird happened to perch on a tomb, as a mere natural hoopoe or swallow. Between the bird-souls and the snake-souls there is this difference. So far as we know, the human-headed bird was purely a creature of mythology, whereas the bearded human snake was the object of a cult. Also the bird-soul, though sometimes male, tends, on the whole, to be a woman; the snake, even when not bearded, is usually the vehicle of a male ghost; as such he is the incarnation rather of the hero than the heroine. So close is the connection that it gave rise to the popular expression ‘Speckled hero,’ which arose, Photius[856] explains, because snakes which are speckled are called heroes. Of these snake-heroes and their cultus Homer knows absolutely nothing, but the belief in them is essentially primitive and recrudesces with other popular superstitions. THE CULTUS-TITLES. The great snake, later worshipped as Zeus Meilichios, was, we have already seen (p. 21), not Zeus himself, but an underworld being addressed by the title Meilichios, gracious, kindly, easy to be intreated. It will now be evident that his snake form marks him as the vehicle or incarnation of a ghost, a local hero. He was only one of a large class of local divinities who were invoked not by proper names but by adjectival epithets, descriptive of their nature, epithets which gradually crystallized into cultus-titles. That these titles were really adjectival is shown sometimes by the actual word, e.g. _Meilichios_, which retains its adjectival sense, sometimes by the fact that it is taken on as a distinguishing epithet by an Olympian, e.g. Zeus-Amphiaraos. These cultus-titles mark an important stage in the making of a god and must be examined somewhat more in detail.