OTHER CITIES OF THE OLD EMPIRE. 435 
is to say, if a hotun-marker, as, for example, Stela 6 at Yaxha, records the 
hotun-ending 9.11.5.0.0, the heavy black line corresponding to Yaxha really 
begins a hotun earlier, 7. ¢., at 9.11.0.0.0, because such monuments, although 
actually erected on the hotun-endings, in reality stood for the entire period 
back to the next preceding hotun-ending. 
Again, if the monument is a lahuntun-marker, that is, when no first or 
third hotun-markers have been found at the site, as, for example, Stela 1 at 
Los Higos, 9.17.10.0.0, the heavy black line corresponding to Los Higos is 
carried back to 9.17.0.0.0, because the lahuntun ending in 9.17.10.0.0 began 
the day following 9.17.0.0.0. 
Finally, if the monument is a katun-marker, that is, when no first, 
second, or third hotun-markers have been found at the site, as, for example, 
Stela 3 at Ucanal, 10.1.0.0.0, the heavy black line corresponding to Ucanal 
is carried back to 10.0.0.0.0, since the katun ending in 10.1.0.0.0 began the 
day after 10.0.0.0.0. 
It follows, then, that the heavy black lines in figure 69 begin a hotun, 
lahuntun, or katun earlier, as the case may be, than the earliest contempora- 
neous date at each site, a necessary condition from the Maya method of reckon- 
ing time in terms of elapsed units; and in using figure 69 this point should be 
constantly borne in mind. Practically, however, this makes little difference in 
the relative lengths of the several periods of occupation, since all the cities 
are treated in the same way, and the maximum error possible when the 
earliest date is a katun-ending is only 15 years, and when it is a lahuntun- 
ending only 5 years. When it is a hotun-ending there is no error at all. This 
possible source of error arises from the fact that when the earliest date is a 
katun-ending, the writer has had to assume in figure 69 that such a monu- 
ment stood for the whole katun, whose ending only it records, whereas it 
may only have stood for a lahuntun or a first or third hotun, giving rise to 
errors of 10, 15, and 5 years respectively, depending upon the practice at 
the site in question. And in the case of a lahuntun-ending, it has been 
assumed that such a monument stood for the whole lahuntun, whereas it 
may only have stood for a hotun, giving an error of 5 years. These are neg- 
ligible quantities, however, when it is taken into consideration that all the 
cities in figure 69, in the very nature of the case, must have been occupied 
some little time, both before and after their earliest and latest contempo- 
raneous dates respectively, and these possible minor errors in no way invali- 
date the comparative value of the data given. 
A few exceptions should be noted. In the case of Quirigua the earliest 
date is really 9.14.13.4.17 as plotted, and not a hotun, lahuntun, or katun 
later, as usually the case in this figure. This date, however, is not a hotun, 
lahuntun, or katun-ending in the Long Count, and probably refers to a 
definite historic or astronomic event. 
In the case of Chichen Itza, although it has only one date in the Old 
Empire, namely, 10.2.10.0.0, its occupation has been extended back surely to 
g.17.0.0.0 on the basis of the chronicle from the Book of Chilan Balam of 
