Human Factor in Plant Evolution 279 



wholesome plants. Some of the native Californian 

 Indians still collect acorns, pine-nuts, and such 

 other wild seeds and berries as they can gather, 

 with grasshoppers, caterpillars, and other similar 

 small game for variety. 



Such wild fruits as the strawberry, huckleberry, 

 cranberry, persimmon, nuts, etc., are much esteemed 

 by everybody, but can hardly be considered as im- 

 portant articles of diet. Among the savage tribes, 

 however, these wild fruits and seeds may be the 

 staple sources of their food supply. The Indians 

 of the Great Lake region used regularly to harvest 

 the wild rice, and the Californian Indians looked 

 upon the oaks and nut-pines as their harvest fields. 

 The South Sea Islander gathers cocoanuts or bread- 

 fruit, and most savages depend to a greater or less 

 extent upon the spontaneous products of a more or 

 less generous nature. 



In the tropics especially, it is hard to draw the 

 line between cultivated and wild plants, as so many 

 of the cultivated fruits, like oranges, mangoes, and 

 bananas, readily escape from cultivation and are 

 often found growing far from any cultivated 

 ground, offering their fruits to whoever may care 

 to gather them. 



Origin of Agriculture. The development of 

 agriculture must have been very gradual and largely 

 a matter of chance. It is more than probable that 

 even in the earliest stages of agriculture and horti- 

 culture, there appeared quite accidentally varieties of 



