446 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 3 3 



Table 1. — The cycles of Mexican chronology 



The Mexican and Central American calendar in the simplified 

 form used outside of Maya territory is clearly the adaptation of 

 Quetzalcoatl. It follows the pattern of the Maya calendar proper, 

 but omits the numerical count of days and the periods which are 

 round numbers in the day count. That is, a permutation of 20 

 names and 13 numbers is used to produce the same short cycle of 

 designations, while the 365-day year is constructed as before out of 

 18 months of 20 days each and 5 extra days. Taking these together, 

 a larger cycle of 18,980 days is produced, essentially the calendar 

 round of the Mayas. But Quetzalcoatl divided this for chronological 

 purposes into a cycle of 52 years of 365 days each and let each year 

 be known by its beginning day, namely, the day which ushered in 



