of these personages are not clear, and it is difficult to find a pictorial representation which can be said with certainty to portray either of them. As regards Mictlantecutli, the god of the underworld, the case is quite otherwise; he is very frequently shown, and nearly always takes the form of a skeleton, often with a stone knife in place of his nose (Fig. 4, b). Skulls and bones are his inevitable accompaniments, the owl is his bird, and his feminine partner was named Mictlanciuatl. Other elemental divinities, of rather nebulous attributes, were the sky-gods Citlalicue and Citlaltonac, who were associated with the creator-gods, the sun and the morning star; and also Yoaltecutli and Yoalticitl, night-deities, of whom the former seems to be identified with the sun and the constellation Gemini, and the latter with Teteoinnan.
We now come to a deity of great importance, the sun, called by the name of Tonatiuh, and the calendrical name of Naui Olin ("Four Movement," Fig. 4, e). This god is easily recognizable by the sun-disc, set about with divergent rays, which he carries, and by his nose-ornament and long quetzal-feathers. Mexican legend recognizes no less than four previous suns, each marking a world period, and each terminating in a convulsion of nature which resulted in a universal destruction. Accounts differ as regards the order of these suns, but the authentic version is probably that which is supported by the so-called "calendar-stone" figured on PL VIII, i, and Fig. 8. According to this version, when all was dark, Tezcatlipoca transformed himself into the sun to give light to men. This sun, known by the calendrical name of Naui Ocelotl (Four Ocelot), terminated in the destruction of mankind, including a race of giants, by jaguars. Quetzalcoatl became the second sun, called Naui Eecatl ("Four Wind"), and the age terminated in a terrible hurricane, during which mankind was transformed into
