a passage from Vergil, in which is described a rite which is really an ‘aversion of evil,’ a kind of purgation by anticipation. Urging the farmer to be religious in the interest of his crops, he says[121]: cui[122] tu lacte favos et miti dilue Baccho, terque novas circum felix eat hostia fruges. The milk, honey and wine here mentioned are the characteristic offerings in the placation of ghosts.[123] The rite was easily transferred to Demeter or Ceres, the Chthonian goddess, because of the natural tendency of Chthonianism to identify the ghost with the god. The ceremony of carrying a victim round the crops was not a symbol of atonement for moral guilt so much as an aversion of quasi-physical evil spirit which caused sterility. Athenaeus,[124] describing the ‘purgation’ of an Arcadian city which was necessitated by the visit of certain citizens from a town which was polluted by bloodshed, says: ‘They made purgation of the city, carrying “victims” round the city territory.’ The similarity of this ceremony to the ‘aversion’ rite described by Vergil is obvious. Yet this ceremony is somewhat different from the purgation of an actual homicide, which we shall describe more fully later.[125] In the former a number of victims are slain; in the latter, only one. Now, if homicide-purgation originated in human sacrifice, and if, as Müller maintains,[126] wergeld was suggested to men by the _de facto_ acceptance, on the part of the gods, of an animal substitute, why was the number of animals sacrificed in homicide-purgation limited to _one_? Why did men not offer to the gods at least the _saraad_ or insult-price,[127] which generally consisted of a number of animals? The sacrifice of only one animal in such a ceremony cannot be explained by Müller’s hypothesis. It can, however, be made intelligible if we assume a direct derivation of the rites of homicide-purgation from the ritual which accompanied solemn oaths and reconciliations. In such a ritual, only a single victim was slain: its death was a kind of inductive symbol of the fate of its slayer, if he ever proved false to his oath. But in ceremonies of general purgation, such as Athenaeus describes, there was an element of expiation, or aversion, and hence there was no limit to the number of victims, for there was no such limit in expiatory sacrifice of any kind.