The position of the American partisans of independent invention is a curious one. It is both weak and strong. Man is inventive—even primitive man. But his inventions often have a unique quality: they are not always duplicated, or they are not duplicated at the same level of cultural development. Consider the cave paintings and the sculpture of the Aurignacians, Solutreans, and Magdalenians in the late Paleolithic. It is an art of remarkable perfection that utterly disappeared, and was not equaled again for thousands upon thousands of years. At Bonampak, in southern Mexico, a Maya painter used consummate perspective and foreshortening long before they appeared in Asia. Then there are the unique Folsom point, the perfection of the Solutrean and Eden points, the Maya calendar and hieroglyphs, the mosaic walls of Mitla in Mexico, Egyptian architecture and sculpture as well as writing, the beautifully expressive masks of the African Negro, the Melanesian, and the Eskimo. These were independent inventions, but they were unique ones. They were not independent, _parallel_ inventions. And they were not diffused. As for early man in the New World, we may believe if we wish that the shape of the Sandia point was diffused from the Solutreans of Europe. We may deny the independent invention in our Southwest of spear-throwers, bull-roarers, bunt points, and curved throwing sticks that look more as if they had been brought from Australia. The Eden point may have come from Siberia, or Siberia may have got it from North America. The Folsom point, however, looks definitely like an independent invention, for it is found nowhere else in the world. This argues that the people who ultimately succeeded in making it must have been in the New World for many, many generations before one of them lashed a Folsom point to a spear and thrust it into a bison. Where are the flints they shaped before the Sandia, Clovis, and Folsom? Can they have evolved the craft of flint knapping here in the New World? When we know this, we shall probably know whether they came before or after the last glaciers. What Diffusion of Plants and Art?