Going back to basketry, we find already the fully developed fret. (See Fig. 553.) I doubt not that from this was evolved, in accordance with Professor Hartt's theory, the scroll or volute as it appears later on pottery. (See Figs. 554, 555.) To both of these designs, and modifications of them ages later, the Pueblo has attached meanings. Those who have visited the Southwest and ridden over the wide, barren plains, during late autumn or early spring, have been astonished to find traced on the sand by no visible agency, perfect concentric circles and scrolls or volutes yards long and as regular as though drawn by a skilled artist. The circles are made by the wind driving partly broken weed-stalks around and around their places of attachment, until the fibers by which they are anchored sever and the stalks are blown away. The volutes are formed by the stems of red-top grass and of a round-topped variety of the _chenopodium_, drifted onward by the whirlwind yet around and around their bushy adhesive tops. The Pueblos, observing these marks, especially that they are abundant after a wind storm, have wondered at their similarity to the painted scrolls on the pottery of their ancestors. Even to-day they believe the sand marks to be the tracks of the whirlwind, which is a God in their mythology of such distinctive personality that the circling eagle is supposed to be related to him. They have naturally, therefore, explained the analogy above noted by the inference that their ancestors, in painting the volute, had intended to symbolize the whirlwind by representing his tracks. Thenceforward the scroll was drawn on certain classes of pottery to represent the whirlwind, modifications of it (for instance, by the color-sign belonging to any one of the "six regions") to signify other personified winds. So, also, the semicircle is classed as emblematic of the rainbow (_a´ mi to lan ne_); the obtuse angle, as of the sky (_a´ po yan ne_); the zigzag line as lightning (_wi´ lo lo an ne_); terraces as the sky horizons (_a´wi thlui a we_), and modifications of the latter as the mythic "ancient sacred place of the spaces" (_Te´ thlä shi na kwïn_), and so on. [Illustration: FIG. 556.--Ancient Pueblo "medicine-jar."]