Flints of Abbevillian and Acheulean types—whether true artifacts or rejects—have been recorded by Kirk Bryan at Cerro Pedernal in New Mexico.[65] At Lake Mohave in the Pinto Basin, Mr. and Mrs. W. H. Campbell have found points of a Mousterian shape and scrapers suggestive of the Aurignacian. They are so crude, however, that they seem more like the “elementary ideas” which, as Bastian claimed, could be the product of primitive man anywhere. In Texas, there are many tools so well developed and so close to Acheulean forms that they cannot be turned aside as either “elementary ideas” or blanks and rejects. These are the hand axes which Sayles and other archaeologists have found.[66] Early Man in Mexico Besides the skull that de Terra found with the fossils of elephants in Mexico, there are artifacts south of the border which reinforce the argument for early man. They are more important than the chance resemblance to a Folsom point which Junius Bird found with sloth bones in a cave in southern Chile, or the Eden-like point which has turned up in Venezuela.[67] During de Terra’s studies of the dry lake beds of the Valley of Mexico and the glacial moraines on the surrounding mountains—studies which began late in 1945—he discovered stone tools in two culture levels. These levels fall in two pluvial periods just before and just after the end of the Great Ice Age. [Illustration: A HAND AX AND A CHOPPING TOOL FROM TEXAS _The dating of these tools is uncertain, but the upper resembles early paleolithic specimens from Europe despite its more flakelike quality. The other is somewhat like chopping tools made from pebbles in Asia and Africa. (Courtesy of Gila Pueblo.)_] The older culture level—called San Juan—contained ten artifacts, including scrapers, gravers, flakes, and chipped pebbles of obsidian and chalcedony and a pointed bone tool, together with fossils of mammoth, sloth, camel, bison, and horse. De Terra found some of this material at Tequixquiac and some near Teotihuacán, where Manuel Gamio came upon fossil bones of mammoth and bison when he was excavating that famous site. Close to where de Terra discovered the skull of early man discussed in Chapter 6, another anthropologist is said to have picked up part of a point of Folsom type—the first to be recorded south of the United States. De Terra places the San Juan culture 12,000 to 20,000 years ago. The younger culture—called Chalco—provided sixty-five variegated artifacts of basalt, including one point. The presence of manos—roundish stones for grinding seeds on a milling stone—as well as other artifacts, causes de Terra to compare this culture with the Cochise in Arizona. He dates the Chalco culture at 4,000 to 10,000 years ago.[68]