Mela speaks of their doctrine of immortality, but says nothing as to the entry of souls into other bodies. As a proof of this belief he speaks of the practice of burning and burying with the dead things appropriate to the needs of the living. Lucan, the Latin poet, in his _Pharsalia_, refers to the seclusion of the Druids' groves and to their doctrine of immortality. The Scholiasts' notes on this passage are after the manner of their kind, and add very little to our knowledge. In Pliny's _Natural History_ (xvi, 249), however, we seem to be face to face with another, though perhaps a distorted, tradition. Pliny was an indefatigable compiler, and appears partly by reading, partly by personal observation, to have noticed phases of Celtic religious practices which other writers had overlooked. In the first place he calls attention to the veneration in which the Gauls held the mistletoe and the tree on which it grew, provided that that tree was the oak. Hence their predilection for oak groves and their requirement of oak leaves for all religious rites. Pliny here remarks on the consonance of this practice with the etymology of the name Druid as interpreted even through Greek (the Greek for an oak being _drus_). Were not this respect for the oak and for the mistletoe paralleled by numerous examples of tree and plant-worship given by Dr. Frazer and others, it might well have been suspected that Pliny was here quoting some writer who had tried to argue from the etymology of the name Druid. Another suspicious circumstance in Pliny's account is his reference to the serpent's egg composed of snakes rolled together into a ball. He states that he himself had seen such an 'egg,' of about the size of an apple. Pliny, too, states that Tiberius Caesar abolished by a decree of the Senate the Druids and the kind of seers and physicians the Gauls then had. This statement, when read in its context, probably refers to the prohibition of human sacrifices. The historian Suetonius, in his account of the Emperor Claudius, also states that Augustus had prohibited 'the religion of the Druids' (which, he says, 'was one of fearful savagery') to Roman citizens, but that Claudius had entirely abolished it. What is here also meant, in view of the description given of Druidism, is doubtless the abolishing of its human sacrifices. In later Latin writers there are several references to Druidesses, but these were probably only sorceresses. In Irish the name _drui_ (genitive _druad_) meant a magician, and the word _derwydd_ in mediaeval Welsh was especially used in reference to the vaticinations which were then popular in Wales.