824 BUREAU OP AMERICAN ETHNOLOOY [Boll. 137 



attached to large tropical land areas from which locusts, boll weevils and other 

 pests come to ravish and destroy the crops. (Article on Climate in Encyclo- 

 paedia of the Social Sciences. ) 



A study of the areas in question, however, seems to indicate that 

 insect pests were a minor element in keeping population down. In 

 Australia the aborigines lived upon foods supplied spontaneously by 

 nature and seem to have been better off than any others on the 

 continent, except perhaps those immediately north and south. The 

 corresponding part of Africa was populated chiefly by Zulus who 

 cultivated the land but, under the influence of the cattle area to the 

 north, considered their herds of more importance. The South Ameri- 

 can territory of this type, like the last two, was in immediate contact 

 with the summer rain belt to the north, but here the highlands were 

 held, not by pastoral people, but by hunters and fishers (the Ge 

 tribes), who also occupied portions of the territory in question, and 

 at a period not remote had extended over considerably more. Agri- 

 culture had worked in along the La Plata and the Brazilian coast and 

 involved the cultivation of corn after the general American manner 

 but in addition the raising of manioc and some other plants. The 

 extension of agriculture in this region seems to have been stimulated 

 in large measure by the northward and eastward spread of the Tiipi 

 from a home in or near Paraguay. The superiority of the farming 

 tribes to the hunters is attested by all writers, and, as exhibited by 

 a tribe like the Caingua, it seems to have brought about conditions 

 like those introduced by the analogous corn culture in North America, 

 greater ease in living conditions, a less migratory existence, and the 

 stimulation of intertribal trade. However, we do not find the higher 

 development of civilization shown by our mound-building tribes, and 

 it may be suspected that this was due to a relatively recent introduc- 

 tion of agriculture. The densest population and apparently the high- 

 est culture was among the Tupi tribes of the Brazilian coast, espe- 

 cially about the present Rio de Janeiro. If insect pests from contigu- 

 ous tropical land areas were a significant item in keeping population 

 down, one wonders why the effects were not apparent in China. 

 Perhaps it is to be partly explained by the chains of mountains along 

 the southern boundary of the republic. Whatever drawbacks existed, 

 they were more than counterbalanced by intensive cultivation, and 

 the use of domestic animals and fertilizer. Our own Southeast was 

 cut off from the corresponding monsoon region of America in a much 

 more complete manner by the Gulf of Mexico and Strait of Florida 

 in the east and desert country farther west. Nevertheless, there is 

 evidence that cultural elements from the south invaded this region 

 from time to time, as we have had occasion to see. The differences 

 exhibited between the manner in which mankind had exploited these 



