Hapi is the ancient Egyptian god of the Nile. He is ancient not only to us of the modern world, but to the Egyptians as well. In fact, "hep", the root of Hapi's name is probably an ancient name for the Nile.
Hapi was portrayed as a man with women's breasts and protruding belly. The full breasts and stomach indicate fertility and his ability to nourish the land through the Nile's annual floods. Just as Egypt was divided into two parts (the north and the south) so was Hapi's domain, the Nile. As a god of the northern Nile, Hapi was depicted wearing papyrus plants, a symbol of Lower Egypt, on his head. In this form, he was called "Hap-Meht". The Nile-god of Upper Egypt was "Hap-Reset" and wore lotus plants (a symbol of the south) on his head. When an artist was attempting to portray Hapi as a god of the entire Nile, he holds both lotus and papyrus plants in his hands or two vases.
The female counterpart and wife of Hapi in the south was Nekhebet, who was a goddess of the south in general and portrayed as a vulture. The wife of the Hapi of the north was Buto, who was depicted as a cobra and the equivalent of Nekhebet in the south.
Osiris was originally a water or river god and eventually Hapi was identified with him. However, in his own right, Hapi was recognized as one of the greatest Egyptian gods and he was declared not only the maker of the universe, but the creator of everything from which it and all things sprang. Hapi was also associated with Nun, as the Nile's source was believed to be located somewhere in the watery chaos of Nun's domain.
Hapi had a certain mysteriousness about him. The Egyptians believed that the Nile rose out of the ground between two mountains (Qer-Hapi and Mu-Hapi) between the islands of Elephantine and Philae. However, the Egyptians had no clue how or why the Nile flooded each year. They believed that the gods Khnemu, Anqet, and Satet were the guardians of the source of the Nile. Their duty was to make sure that the right amount of silt was released during the yearly inundation. Hapi was in charge of the waters that flowed during the floods. The flood was commonly known as the "arrival of Hapi". The Egyptians would toss sacrifices, amulets and other offerings into the Nile at special places to appease Hapi and to ensure that he would provide an adequate inundation to water their fields. (Egyptian myths)