pictorial stage, one of which the student of native American culture needs to take little cognizance.

Elements of design are not invented outright: man modifies, combines, and recombines elements or ideas already in existence, but does not create.

A classification of the sources of decorative motives employed in the ceramic art is given in the following diagram:

SUGGESTIONS OF NATURAL FEATURES OF OBJECTS.

The first articles used by men in their simple arts have in many cases possessed features suggestive of decoration. Shells of mollusks are exquisitely embellished with ribs, spines, nodes, and colors. The same is true to a somewhat limited extent of the shells of the turtle and the armadillo and of the hard cases of fruits.

These decorative features, though not essential to the utensil, are nevertheless inseparable parts of it, and are cast or unconsciously copied by a very primitive people when similar articles are artificially produced in plastic material. In this way a utensil may acquire ornamental characters long before the workman has learned to take pleasure in such details or has conceived an idea beyond that of simple utility. This may be called unconscious embellishment. In this fortuitous fashion a ribbed variety of fruit shell would give rise to a ribbed vessel in clay; one covered with spines would suggest a noded vessel, etc. When taste came to be exercised upon such objects these features would be retained and copied for the pleasure they afforded.