Many stone vessels were made. They were usually carved in bas relief and both realistic and life-forms were used. Desert reptiles were the most common figures. Other objects made of stone included abraders for use in shell work, metates which were not very precisely shaped, a few stone finger-rings, and projectile points. These were long slender points which were barbed and serrated. [Illustration: Fig. 45—Hohokam carved stone vessel of the Colonial period. (Courtesy Arizona State Museum.)] [Illustration: Fig. 46—Hohokam ornaments of carved shell. (Courtesy National Park Service.)] Shell was very widely used. A few needles made of shell have been found, but this was apparently not considered a utilitarian material and it was most often used in the manufacture of ornaments. Shell beads and pendants continued to be used, and many bracelets were made. These were made of Glycymeris shells which are nearly circular and, when cut in cross-section, provide a suitable arm band. Carving did not reach its peak until the following period, but fine bracelets were produced. Birds, snakes, frogs, and geometric forms furnished the designs. The most frequent motif is a bird-and-snake combination. The snake’s head is in the bird’s mouth and the body of the snake forms the band. This quite probably had some special ceremonial significance. Carved rings, which first appeared at this time, are usually in the form of snakes. They were never as abundant as bracelets. There was some mosaic work with shell, but this art did not fully develop until later. Birds and snakes, often in combination, were the usual subjects for carving on bone. THE SEDENTARY HOHOKAM During the Sedentary period, which lasted from about 900 to 1200 A. D. there was some withdrawal from the outlying districts and a greater concentration of population in a smaller area, although there was also some northward extension of the culture. There was some regional specialization during the latter part of the period, for the inhabitants of the upper or eastern portion of the Gila Basin developed somewhat differently from those of the central area. This was possibly the result of the influence of Pueblo people who lived in the Tonto Basin about one hundred miles to the northwest, and it presaged the changes which were to occur in the next period when some of these people moved into the Hohokam area, bringing with them their distinctive culture.