ge of the Cordilleras drew in general a dividing line between
the eastern and western tribes.[776] Though Athapascans from the east
overstepped it at a few points in North America, the Great Divide has
served effectually to isolate the two groups from one another and to
draw that line of linguistic cleavage which Major Powell has set down in
Ms map of Indian linguistic stocks. Consequently, Americanists recognize
a distinct resemblance among the members of the North Atlantic group of
Indians, as among those of the South Atlantic group; but they note an
equally distinct contrast between each of them and its corresponding
Pacific group. Nor is this contrast superficial; it extends to physical
traits, temperament and culture,[777] and appears in the use of the
vigesimal system of enumeration in primitive Mexico, Central America,
among the Tlingits of the Northwest coast and the Eskimo as also among
the Chukches and Ainus of Asia, while in the Atlantic section of North
America the decimal system, with one doubtful exception, was alone in
use.[778]

[Sidenote: Cultural superiority of the Pacific slope Indians.]

To the anthropo-geographer, the significant fact is that all the higher
phases of native civilization are confined to the Pacific slope group of
Indians, which includes the Mexican and Isthmian tribes. From the
elongated center of advanced culture stretching from the Bolivian
highlands northward to the Anahuac Plateau, the same type shades off by
easy transitions through northern Mexico and the Pueblo country,
vanishes among the lower intrusive stocks of Oregon and California, only
to reappear among the Haidas and Tlingits of British Columbia and
Alaska, whose cultural achievements show affinity to those of the Mayas
in Yucatan.[779] Dall found certain distinguishing customs or
characteristics spread north and south along the western slope of the
continent in a natural geographical line of migration. They included
labretifery, tattooing the chin of adult women, certain uses of masks, a
certain style of conventionalizing natural objects, the use of
conventional signs as hieroglyphics, a peculiar facility in carving wood
and stone, a similarity of angular designs on their pottery and
basketry, and of artistic representations connected with their common
religious or mythological ideas. Many singular forms of carvings and the
method of superimposing figures of animals one upon another in their
totem poles are found from