We see by reference to the annexed table of years (XXIII), which contains exactly one cycle, that by commencing at the bottom of the right-hand or Ix column and running up, we find the numbers given in the quotation and in precisely the same order. As these figures mark the terminal years of the lustres 
it is evident that the authority quoted applied the name "Katun" to these periods, and that this word is not used here as an equivalent of "Ahau."
If the series began with Gauac, as shown by this table, these numbers would then denote Ix years; but if it commenced with Kan they would then be Cauac years. In either case it is evident that by remembering these numbers and their order it would be an easy matter to locate or give the number of any year in the cycle, and in the grand cycle also, if they had any method of numbering the cycles. But I am unable to see how this could be of much service in counting the Ahaues, and am therefore inclined to believe that this method of counting back was chiefly in vogue among the common people, they being unable to fully understand and use the complicated calendar of the priests. Although Landa, when speaking of the facility with which they counted back the years, evidently alludes to the Ahaues, yet it is quite probable the old Indian who traced back their history for three hundred years did so by the use of this key, unless he was a priest.
It is difficult to understand what is meant by the expression "they fall on the two days of Uayeb haab" [intercalated days].
In the four plates of the Dresden Codex heretofore mentioned (25-28), which certainly refer to the feasts of the intercalated days, we notice that the left-hand column of each contains the characters of but two days—the 25th the days Eb and Ben, the last two of the intercalated days of the Muluc years; the 26th, Caban and Ezanab, the last two of the Ix years, and so on.
Although these, as here noted, may not have any reference to this
