Note 3 — THE TONALAMATL AND THE SOLAR CALENDAR

Each of the 20 tonalamatl divisions, or “weeks” of 13 days each, as they are sometimes erroneously but usefully designated, had also a patron god of its own which ruled over its fortunes. The initial days of these “weeks” gave the name to the entire “week,” therefore the designation of the 20 weeks was the same as that of the 20 day-signs; but the “weeks,” or rather the week-names, did not follow each other in the same incidence as the days, as will be seen from the foregoing table. The patron gods of the 20 weeks were, however, the same as those of the 20 days, with this exception, that whereas the gods of the first 10 day-signs were taken also as the rulers of the first ten weeks,3 the god of the eleventh day, Xochipilli, was allowed to drop out, the god of the twelfth day, Patecatl, taking his place, the god of the thirteenth day taking the twelfth place, and so on, the deficiency in the twentieth place being made up by adopting Itztli and Xiuhtecutli as joint gods of the twentieth “week.” The list of gods of the “weeks” would thus be as follows: