286 Plant Life and Evolution 



unknown in the wild condition, but there are certain 

 grasses related to maize which it has been surmised 

 may possibly be the wild plants from which the culti- 

 vated maize has arisen. 



Fruits. In some countries grains are replaced 

 to a great extent by fruits like the banana 

 and breadfruit, or tubers like the taro or the po- 

 tato. The banana in its many forms has been 

 cultivated from the earliest times in the Asiatic 

 tropics, and Humboldt states that it was culti- 

 vated in America prior to its discovery by 

 Columbus; but this seems to be very doubtful, 

 as all wild bananas are Asiatic and it seems 

 practically certain that the banana was introduced 

 into America shortly after its discovery by Euro- 

 peans. As the cultivated bananas are seedless, their 

 spread into foreign countries is absolutely dependent 

 upon human agency. The same is true of the 

 breadfruit, which has been carried from its home 

 in Java to all of the moister regions of the trop- 

 ics. It is quite common to find the breadfruit and 

 banana growing far away from human habitations, 

 and this is true also of the taro, which is known in 

 the wild state in the warmer parts of the Indo- 

 Malayan regions. It has been carried by the Poly- 

 nesians to all the warmer parts of the South Seas, 

 and is still a very important article of diet among 

 the Hawaiians. The potato was cultivated in Amer- 

 ica, especially in the mountain regions of South 

 America, long before the advent of the Europeans. 



