MODIFICATION AND DISTRIBUTIONS OF CROPS 239 



North and South American types. Other Strawberries have long 

 been grown elsewhere, the fruit as a whole being a favourite in all 

 temperate countries. In contrast, Pineapples, Bananas, and Melons 

 are mainly tropical types of ancient origin. The Malay Peninsula 

 appears to have been the chief centre of origin of cultivated Bananas, 

 whereas South America gave us the Pineapple, and Africa or southern 

 Asia various Melons ; but all three types are now grown practically 

 around the globe. 



(7) Other Crops — Especially important among these are Tobacco 

 {Nicotiana tabacum) and Sugar Cane {Saccharum officinarum), while 

 the Hop (Hiimulus lupulus) and \arious Buckwheats {Fagopyriim 

 spp.) are of no mean significance in some areas. Tobacco is 

 apparently a true-breeding polyploid hybrid between two weedy 

 inhabitants of South America, where it probably arose in cultivation 

 in early pre-Columbian times. Now it is grown extensively in 

 various of the sufficiently summer-warm regions around the globe, 

 as indicated in Fig. 74, and is an important commodity throughout 

 the inhabited world. Sugar Cane, a vigorous-growing perennial 

 Grass, is the chief source of sugar at present, although at times in 

 the past it has been rivalled by Sugar Beets. Sugar Cane probably 

 originated in southeastern Asia and comprises an assemblage of 

 forms that are unknown in the wild state but are now cultivated in 

 practically all moist tropical and subtropical regions, the main areas 

 of production of sugar from it and from Sugar Beets being indicated 

 in Fig. 75. Cane sugar probably constitutes the greatest export 

 crop of the tropics. 



(8) Razv Materials for Industrx — A large proportion of these are 

 afforded by plants in limitless supply. This category largely cuts 

 across the others, which in most instances contribute familiar 

 examples to it, and so we need scarcely add details. Suffice it to 

 say that industrially important raw materials include not only the 

 examples already mentioned, such as various grains, roots, fibres, 

 oils, carbohydrates and their derivatives, but also a wide range of 

 forest products including rubber and pulp. The field-crops involved 

 are grown in the main crop-producing parts of the world and the 

 forest products are obtained mostly in major forested regions. 

 Further information about the sources of these all-important raw 

 materials supplied by plants will be found in the books cited at the 

 ends of this chapter and the succeeding one which stresses further 

 their vital economic significance. 



