OTHER CITIES OF THE OLD EMPIRE. 441 
Class 4 is by no means exhaustive; it contains only those small sites 
where inscriptions have been found, and in the very nature of the case it 
could be expanded to many times its present size if all the smaller known 
ruin-groups were included therein. Within the individual classes the order 
of the cities is chronological. 
Crass I (2). Crass II (6). Crass III (6). Crass IV (21). 
Hakal. Piedras Negras. Uaxactun. Altar de Sac.—El Pab. 
Copan. Naranjo. Yaxha. Tzendales. 
Palenque. La Honradez. Chichen Itza. 
Yaxchilan. Seibal. Itsimte. 
Nakum. Ixkun. El Cayo. 
Quirigua. Undated inscriptions. La Mar. 
Ocosingo. Aguas Calientes. 
Cancuen. 
Ucanal. 
Benque Viejo. 
Flores. 
Quen Santo. 
Los Higos 
Undated inscriptions. 
Chunvis. 
FE] Encanto. 
San Jose de Motul. 
Rio Grande. 
Rio Amarillo. 
Chinikiha. 
El] Chicozapote. 
Xupa. 
The curve of the growth and expansion of the Maya civilization during 
the Old Empire, based upon the frequency of the dated monuments, is 
shown in figure 70. The abscisse of the curve are the successive hotuns of 
the Long Count from 8.14.0.0.0 to 10.3.0.0.0, shown by the vertical lines 
as in figure 68, every fourth line, corresponding to a katun-ending, being 
heavier. 
The ordinates of the curve are the number of times any given hotun- 
ending is recorded on different monuments. Monuments bearing dates 
other than hotun-endings, as, for example, 8.14.10.13.15 on Stela 9 at 
Uaxactun or 9.2.13.0.0 on Stela 3 at Tikal, have been plotted in this figure 
as dating from their current hotun-endings, 7. ¢., as 8.14.15.0.0 and 9.2.15.0.0 
for the above two stele respectively. The most notable features of the curve 
ates 
1. The practically stationary condition throughout the Early Period, perhaps 
due to the labors involved in conquering the new environment. 
2. The sudden rise just at the end of the Early Period, perhaps indicating 
that sufficient reserves had been accumulated to extend the sphere of occupation. 
3. The gradual rise from this point to the maxima in 9.17.0.0.0 and 9.18.0.0.0, 
at the height of the Great Period, indicating the normal growth and expansion of a 
people who had mastered the different problems presented by their environment. 
4. The absence of any stations on the curve from 9.19.15.0.0 to 10.0.15.0.0, 
inclusive, indicating the entire absence of monuments dating from these 5 hotuns. 
