"The Aztecs, who received most of the credit in the popular mind for the achievements on cultural lines in Mexico, were very late arrivals on the scene. It was not until 1325 that they reached the shores of that lake on an island in which they were later to build their capital.

Some Early Events Unknown

"There are several dark spots on the picture I have tried to draw. We do not know what led the Mayas to abandon their great cities in the south and move northward. The exhaustion of the cultivable land may have been one of the reasons. We are also ignorant as to the events which led up to the fall of this civilization about 1450. Civil war, the injurious effects of the presence of foreigners and in all probability epidemics of yellow fever were contributory.

Mayas Not Related to Asiatics

"The darkest spot in our knowledge of the history of the Mexican natives is our ignorance of the beginnings of the Maya peoples. It is certain that those responsible for this civilization were American natives and that their development is not due to any influence outside the new world.

"The impossibility that such a culture could grow up in situ, as it were, is always brought forward by those who think they see superficial similarities between the Mayas and certain Mongolian peoples. The calendar alone, which no one has tried to prove originated outside of America, shows the mental equipment of the Mayas, the presence of genius in their midst.

Study Induces Readjustments

"Finally, as the result of modern research a certain readjustment of values comes out clearly, the small contribution made by the Aztecs to the ancient cultures of Mexico, the large part played by the Toltecs with their far reaching empire and the far greater primary impetus and development of a great civilization and calendar by the Mayas.