Digestion, Transfer, and Accumulation of Foods 79 



large sugar content ; field corn was developed through the 

 selection of seeds for starch content. The original sugar 



P2.2 yr. 78.3 



BANANA 



135- 

 Ash.l.4---WpAT?SNrP CORM '^'^-A.14 



WALNUT A.O.a^ 



Fig. 49. Diagrams showing percentages of water, protein, fat, carbohydrate, and ash 

 in various plant organs. Note the low percentage of water ifi seeds as well as the 

 similarity of content of the potato and the banana. _ 



beets contained less than 5 per cent of sugar; because of 

 careful seed selection and intelligent fittiag of the environ- 

 ment to the plants, the best quality of beets grown today con- 

 tains as high as 22 per cent. The original potato tubers 

 weighed about an ounce; potatoes weighing several pounds 

 are now grown, and a plant may produce ten times as many 

 tubers as are produced by the original plant. 



The testing of wild species of plants for possible cultiva- 

 tion and use as sources of food, and the introduction of species 

 cultivated in other countries, is being carried on by govern- 

 ments in all parts of the world. Through its agricultural ex- 

 plorers the United States has probably accompKshed more 



