Histoire Naturelle - Birds - Plate 7 - Ibis ~ The ibis, or Threskiornis aethiopicus, was the 'Sacred Ibis of Egypt' and is pictured here on the right. By the ancients, it was called 'hib', hence 'hibis' or 'ibis'. The bird on the left is Plegadis falcinellus, the black ibis or 'gemet' to the ancient Egyptians. Both of these were waterside birds and represented the sacred birth of Thoth, the god of knowledge, who had the form of an ibis-headed man. The Ibis was common throughout Egypt until the 19th Century, but now has almost disappeared. They were mummified during the Late Period and Ptolemaic times, and buried in large numbers in different catacombs through Egypt. The ibis was considered sacred because its arrival each year coincided with the flooding of the Nile River. The Nile provided irrigation for crops, and the ibis became a symbol for the bounty of the river.