The descent of the clan from the Totem-animal, or of the animal from a forefather of the clan, or of both from a _tertium quid_, involves metamorphosis; and this, again, is not itself a magic idea; for real metamorphoses are common in the life of birds, amphibia, insects, and it would be unreasonable to expect savages to perceive clearly that these are not parallel cases. There is a difference, however, between transformations that may be observed, such as that of a chrysalis into a butterfly, and those that have never been observed, but are merely imagined and asserted. The latter are more mysterious, and mystery is one character of magic. For example, the Witchety-Grub clan among the Arunta have as their mate a bird, the chantunga, which they will not eat because, they say, of old some full-grown witchety-grubs were transformed into these birds.[535] This change has a magical character, though no magical agency is assigned. But if any attempt were made to explain how the great change took place, recourse might be had to powers of magic. Even when agency is assigned, it is not always magical. In the earliest Alcheringa the two Ungambikula (“out of nothing”) saw in groups by the shore of the salt water a number of inapertwa, rudimentary men, mere roundish masses, without organs or means of feeding, and these they cut out into men with stone knives, therefore not by magic.[536] But, again, a tribe on the Darling River (Wathi-wathi) have traditions concerning Bookoomuri who lived long ago, excelled in Magic, and transformed themselves into animals; and here the magical power is asserted, though the manner of its operation is indefinite. But the Bear clan of the Tshimshians (British Columbia) explain their position by the story that once upon a time an Indian, whilst hunting, met a bear, which took him to its home, where he stayed two years. On returning to his village he looked like a bear; but, having been rubbed with medical herbs, recovered human shape.[537] And here the magic is as explicit as in any recipe for a were-wolf, or that fallacious ointment with which Lucius achieved his memorable transformation.