CELL-CONTENTS AND FORMS OF CELLS. 



199 



class of chemical substances designated as " polypeptides " which 

 are formed by the condensation of several amino acids. 



The Percentage of Protein in Plants. — The amount of 

 protein in plants varies considerably. It is found in greatest 

 amounts in seeds, especially in the seeds of the Leguminosee and 

 the grains of cereals. It is also found in surprisingly large quanti- 

 ties in a number of the vegetables. Were it not for the fact that the 

 fungi contain large quantities of water, they would be considered 

 the most nutritious of all vegetable foods, as they contain in dry 

 substances over 50 per cent, of protein. As the fresh mushrooms, 

 however, contain nearly 90 per cent, of water, this brings the pro- 

 tein content to but about 5 per cent. The percentage of protein 

 in dried material from a number of sources may be of interest, as 

 follows : 



Grains or Cereals. — Barley, 7.64 to 17.90; buckwheat, 9.75 to 

 17.25; corn, 6.41 to 17.02; oats, 8.35 to 21.88; rye, 8.39 to 17.38; 

 rice, 6.49 to 12.81 ; and wheat, 8.30 to 27.88. 



Leguminous Seeds. — Kidney beans, 22.53 to 36.46; lentils, 

 14.58 to 34.34; lima beans, 15.94 to 25.63; Lupinus luteus, 15.62 

 to 61.27; peanut, 25.39 to 33.73; peas, 21.59 ^^ 32.94; soja beans, 

 24.38 to 49.10; string beans, 13.06 to 20.19; and Vicia faba, 21.00 

 to 36.10. 



Miscellaneous Seeds. — Beechnut, about 25 ; cacao, 7.32 to 

 15.94; cocoanut, 7.75 to 10.90; chestnut, 5.15 to 15.75; hazel-nut, 

 16.23 to 21.22; flaxseed, 18.49 to 33.80; mustard, 15.50 to 39.66; 

 coffee, 17.11 to 25.09; rape-seed, 15.18 to 28.13; ricinus, 16.35 to 

 22.28; sunflower-seed, 5.67 to 33.89 ; sweet almond, 17.50 to 26.62. 



Common Vegetables. — Asparagus, 15.12 to 33.52; sugar beets, 

 3. II to 23.02; garden beets, 4.19 to 29.27; carrots, 3.79 to 16.64; 

 cauliflower, 17.23 to 37.75 ; celery, 8.44 to 25.19 ; cucumber, 21.38 to 

 26.06; garlic, 1. 17 to 13.50; parsnips, 6.38 to 13.50; potatoes, 2.21 

 to 17.59; sweet potatoes, 1.70 to 19.61 ; radish, 13.00 to 22.13; 

 spinach, 27.50 to 45.33; and turnips, 4.01 to 21.00. 



Fruits. — Apples, 0.22 to 1.32; apricots, 0.13 to 1.79; bananas, 

 3.37 to 7.75; cherries, 0.97 to 4.75; cucumber, 21.38 to 26.06; 

 currants, o.ii to 1.44; figs, 0.90 to 2.58; gooseberries, .21 to .94; 

 grapes, 0.22 to 1.20; lemons, 0.49 to 2.90; musk melon, 4.69 to 

 22.23; oranges, 4.83 to 2.24; peaches, 0.23 to 1.67; pears, 0.19 to 



