points upon
both the plastic and the sun-dried clay, as well as at times upon
the fire-baked surface. Figures thus produced exhibit a wide range of
artistic achievement. They illustrate all stages of progress from the
most archaic type of ornament--the use of dots and straight lines--to
the most elegant combinations of curves; and, finally, to the
delineation of life forms and fanciful conceptions.

Generally, when a blunt implement is employed, the line is produced
by a movement that I shall call _trailing_, in contradistinction
to _incision_, in which a sharp point is used, and _excision_ or
_excavation_, which is more easily accomplished with the end of a
hollow reed or bone. _Impressed_ or _stamped_ ornament is of rare
occurrence, and anything like _repoussee_ work is practically unknown.
The practice of impressing cords and fabrics was common among many of
the northern tribes, and nets have been used in the manufacture and
ornamentation of vases at many points within this province. The use of
stamps, especially prepared, was in vogue in most of the Gulf States,
and to a limited extent in northern localities.

_Designs in color._--The colors used in painting are white, red,
brown, and black, and have generally consisted of thick, opaque,
clayey paste, white or colored with ochers. Occasionally the colors
used seem to have been mere stains. All were probably laid on with
coarse brushes of hair, feathers, or vegetable fiber. The figures are
in most cases simple, and are applied in broad, bold lines, indicative
of a strong talent for decoration. The forms are, to a great extent,
curvilinear, and embrace meanders, scrolls, circles, and combinations
and groupings of curved lines in great variety. Of rectilinear forms,
lozenges, guilloches, zigzags, and checkers are best known.

The decided prevalence of curved forms is worthy of remark. With all
their fertility of invention, the inhabitants of this valley seem
never to have achieved the rectangular linked meander, or anything
more nearly approaching it than the current scroll or the angular
guilloche, while other peoples, such as the Pueblos of the Southwest
and the ancient nations of Mexico and Peru found in it a chief
resource. The reasons for this, as well as for other peculiarities of
the decorative art of the mound-builders as embodied in pottery, must
be sought for in the antecedent and coexistent arts of these tribes.
These peoples were certainly not highly ac