and Navajo, the former of whom have gained a strong foothold in northern
Mexico, while the Tañoan, a Pueblo family of the upper Rio Grande, has
established a few pueblos lower down the river in Mexico. For the
purpose of necessary comparison, therefore, the map is made to include
all of North America north of Mexico, the entire peninsula of Lower
California, and so much of Mexico as is necessary to show the range of
families common to that country and to the United States. It is left to
a future occasion to attempt to indicate the linguistic relations of
Mexico and Central America, for which, it may be remarked in passing,
much material has been accumulated.

It is apparent that a single map can not be made to show the locations
of the several linguistic families at different epochs; nor can a single
map be made to represent the migrations of the tribes composing the
linguistic families. In order to make a clear presentation of the latter
subject, it would be necessary to prepare a series of maps showing the
areas successively occupied by the several tribes as they were disrupted
and driven from section to section under the pressure of other tribes or
the vastly more potent force of European encroachment. Although the data
necessary for a complete representation of tribal migration, even for
the period subsequent to the advent of the European, does not exist,
still a very large body of material bearing upon the subject is at hand,
and exceedingly valuable results in this direction could be presented
did not the amount of time and labor and the large expense attendant
upon such a project forbid the attempt for the present.

The map undertakes to show the habitat of the linguistic families only,
and this is for but a single period in their history, viz, at the time
when the tribes composing them first became known to the European, or
when they first appear on recorded history. As the dates when the