A Botanical and Economic Study. 95 



ence to the offshoots, it is necessary for perennial growth of 

 a plant so sensitive as maize to frost, to live in a tropical 

 climate, where the suckers can be produced with the greatest 

 advantage to the plant. 



Otis T. Mason believes that the original habitat of the 

 maize is to be found in regions where the grains remain 

 unharmed out of doors over the winter m6nths ; for the grain 

 decays if left out in the fields in the United States exposed 

 to the destructive effects of the cold and ice. He believes 

 that a semi-arid region answers the conditions most satisfac- 

 torily. The anatomy of the leaf points to the same conclusion, 

 for the lower epidermis is thickened to protect the leaf and 

 prevent too rapid transpiration, when the leaf is rolled up by 

 the loss of water in the bulliform cells. 



The Maya civilization was not a growth of chance, but was 

 dependent for its origin on the surrounding circumstances, 

 propitious to such a development ; the physical and biological 

 features of the country influenced the settlement. The pla- 

 teau of Mexico has a favorable climate and naturally yields a 

 variety of products. On it grow the agave from the bud of 

 which a drink is brewed, cacao which furnishes the beverage 

 chocolate, the potato, the tobacco plant, the sweet sop (Anoua 

 vntricatd), papaw {Carica Papaya), nopal {Opuntia cocJiinclli- 

 ferd) on which the cochineal insect feeds, guava and caoutchouc 

 (JJevea brasiliensis). The plants mentioned are all natives 

 of the warmer parts of North America, and it is likely that 

 maize also occurred in the same region in the wild state, and 

 was one of the first plants of economic importance to be cul- 

 tivated. The Mayas depended chiefly upon maize and honey 

 for their food, and there is hardly a doubt that the natives 

 were attracted to the warm plateau of Mexico, where the 

 country was so inviting and rich in natural vegetal products. 

 These facts point to the Mexican origin of maize. 



C. ArcJiaological Proofs. 



The accounts are numerous as to the discovery of Indian 

 corn in places of undoubted pre-Columbian antiquity, but 

 they are general, and for the most part unsatisfactory. When 



