Working where possible from the known to the unknown, I have attempted to discuss two symbols that relate to time in Nahuatl religion: the "dragon" and the dog. In so doing it was possible, indeed necessary, to point out a series of interlocking complexes which comprise both representations. I have tried to show that the "dragon" or earth monster as a symbol goes far beyond its more obvious association with the surface of the earth, and is in fact connected with many other related kinds of symbols-in particular those having to do with such ideas as beginning, creation, the East, and (as the serpents Quetzalcóatl and Xiuhcoatl) with both time and the cosmos. Similarly, in the case of the dog, the series of complexes included such things as the underworld, the night sun, fire and movement, the Pleiades, and the West. I have suggested that the Quetzalcóatl/Xiuhcoatl serpents are connected with both the solar year and the sacred calendar round of 260 days, and that the figure of Quetzalcóatl/Xólotl indicates yet a further connection with the cycles involving the planet Venus. We have thus explored, albeit in somewhat brief compass, two ways in which the sense of time has manifested itself in Nahuatl culture: the structure of that meaning, and the response to it.