southward it does not appear in our collections. The significance of this is not yet clear. The data for the eastern maize area show us that the agricultural pattern was to hoe up hills around the plants. As stated before, maize, squashes and beans were often put in the same hill. Tobacco was planted in hills and so were the sweet potatoes of the south. The first Atlantic colonists adopted the hoe pattern of the native, especially in the south, where to some extent it still survives.
Artificial fertilization was practised from Nova Scotia to Chile. One method, widely distributed in both continents, was the placing of fish in the maize hill. Manures, both human and animal, were used in parts of the area of intensive agriculture. So particular a correspondence as planting with fish, reported for localities between New England and Peru, points clearly to a common origin, but it is the study of the maize plant itself that affords the strongest argument for diffusion from one center. The investigations of Harshberger[1] and Collins[2] indicate that maize was developed from a wild grass of the Maya habitat. The distribution from this center of varieties once so developed would readily account for the uniformity of maize culture we have noted. Unfortunately, no careful study of the aboriginal varieties of maize has been made, but the data at hand suggest that about all the distinct kinds we still have on our farms were in existence by 1492 and that they existed side by side in the same fields. The time required to stabilize all these forms and the subsequent precision of domestic routine that preserved their racial integrity to the present among some of the surviving natives, is one of the most impressive facts of our subject.
So brief a review as this must needs pass over in silence many interesting points, but we should give passing notice to the evidence for the local adaptation of these widely distributed varieties of maize. Wilson[3] has shown that the Hidatsa of the upper Missouri have trained certain varieties to ripen early and within the limits of the short season, a characteristic the maize of our eastern farms does not manifest. Collins[4] makes clear that the Pueblo tribes of New Mexico and Arizona have developed varieties with long, deep-
