The case of the phœnix or _bennu_ is somewhat different. Here we have to do not with a fabulous monster, but with an existing bird of which a fabulous story was told. The bird was not an eagle, as Herodotos supposed, but a heron, which at an early date seems to have been confounded with the crested ibis, the symbol of the _khu_ or luminous soul. It was, in fact, the spirit of the sun-god, and later legends declared that it stood and sang on the top of a tree at Heliopolis, while a flame burst forth beside it, and the sun rose from the morning sky. With sunset it became an Osiris, whose mummy was interred at Heliopolis, to awake again to life with the first rays of the rising sun. It was thus for Christian writers an emblem of the resurrection, and as such its story is told by St. Clement of Rome:(81) “There is a certain bird which is called the phœnix. This is the only one of its kind, and it lives five hundred years. When the time of its dissolution draws near that it must die, it builds itself a nest of frankincense and myrrh and other spices, into which, when the time is fulfilled, it enters and dies. But as the flesh decays a certain kind of worm is produced, which, being nourished by the juices of the dead bird, brings forth feathers. Then, when it has acquired strength, it takes up the nest in which are the bones of its parent, and, bearing these, it passes from the land of Arabia into Egypt, to the city called Heliopolis. And, flying in open day in the sight of all men, it places them on the altar of the sun, and, having done this, it hastens back to its former abode. The priests then inspect the chronological registers, and find that it has returned exactly when the five hundredth year is completed.”(82) The legend of the phœnix has grown up round the belief that the disembodied soul could enter at will into the body of a bird. The phœnix was allied to the hawk of Horus, and probably was originally identical with that primitive symbol of the soul (_khu_), the name of which means literally “the luminous.” It will be remembered that the Pyramid texts speak of the “four _khu_” or “luminous souls of Horus” “who live in Heliopolis,” and the sun-god of that city was usually invoked by his _bau_ or “souls,” figured as three birds which appear as three ostriches on objects found in the tomb of Menes.(83) On an early seal-cylinder of Babylonian type the _bennu_ or _khu_ is termed “the double of Horus.”(84)