Schurtz^[1] and by Professor A. D. F. Hamlin,^[2] who has treated in a series of essays the evolution of decorative motives.

In speaking of the process of conventionalization or degeneration of realistic motives, Professor Hamlin says: "Indeed, this degeneration may reasonably be accepted as suggesting that the geometric forms which it approaches were already in habitual use when it began, and that the direction of the degeneration was determined by a

Fig. 16. Shamanistic Coat of Eskimo.

preexisting habit or 'expectancy' (as Dr. Colley March calls it) of geometric form acquired in skenomorphic decoration"^[3] (i. e., in a form developed from technical motives). At another place^[4] he says: "After having undergone in its own home such series of modifications, the motive becomes known to the artists of some race or