Benoo (Eg.). A word applied to two symbols, both taken to mean “Phœnix”. One was the Shen-shen (the heron), and the other a nondescript bird, called the Rech (the red one), and both were sacred to Osiris. It was the latter that was the regular Phœnix of the great Mysteries, the typical symbol of self-creation and resurrection through death—a type of the Solar Osiris and of the divine Ego in man. Yet both the Heron and the Rech were symbols of cycles; the former, of the Solar year of 365 days; the latter of the tropical year or a period covering almost 26,000 years. In both cases the cycles were the types of the return of light from darkness, the yearly and great cyclic return of the sun-god to his birth-place, or—his Resurrection. The Rech-Benoo is described by Macrobius as living 660 years and then dying; while others stretched its life as long as 1,460 years. Pliny, the Naturalist, describes the Rech as a large bird with gold and purple wings, and a long blue tail. As every reader is aware, the Phœnix on feeling its end approaching, according to tradition, builds for itself a funeral pile on the top of the sacrificial altar, and then proceeds to consume himself thereon as a burnt-offering. Then a worm appears in the ashes, which grows and developes rapidly into a new Phœnix, resurrected from the ashes of its predecessor.
Source: H.P.Blavatsky - The Theosophical Glossary