548 BOTANY OF THE LIVING PLANT 



Wheat {Triticitm vulgare, Villars) has been cultivated from pre- 

 historic times in Europe and Egypt, and in China records of it go back 

 to 2700 B.C. It is represented by numerous varieties. Those in which 

 the ripened grain detaches itself naturally from the husk are referred to 

 one species {Triticum vulgare. Villars) ; those in which the ripe grain 

 is closely contained in the husk are distinguished as Spelts (T. Spelta. L.). 

 The separation of these was probably prehistoric. There is no certain 

 evidence of the place of origin of wheat, for it is not found wild, but 

 its probable home was in the Near East. It is the chief staple food of 

 the white races. 



Rye {Secale cereale, L.) probably had its origin in the countries north 

 of the Danube, and its cultivation was hardly earlier than the Christian 

 era. It does not greatly differ in its nutritive qualities from wheat, 

 and is largely grown in central and northern Europe. 



Barley {Hordeum distichon, L., vulgare, L., and hexasticJion, L.) is 

 among the most ancient of cultivated plants. It has been found wild 

 in the Caspian region. It is chiefly used for malting and brewing, for 

 which its low content of proteids is suitable. 



The Oat {Avena sativa, L.) is not now found wild, but it was probably 

 derived from a form native in Eastern Temperate Europe. It was 

 cultivated anciently in Italy and Greece, and its grains have been found 

 in Swiss lake-dwellings, and in early German tombs. Though a coarse 

 grain with much cellulose and lignin in its outer coats (10 to 12 per cent.), 

 its high percentage of fats (5 to 6 per cent.), proteids (12-13 per cent.), 

 and ash (3 to 4 per cent.), mark it as superior to any other Cereal as a 

 staple food. Moreover, a comparison of the average of analyses of 

 Oats from all sources with those from England and Scotland shows 

 that these stand the highest of all ; a fact which justifies, and should 

 encourage, the prevalent use of porridge and oat-cake. 



Maize {Zea Mays, L.) is of American origin. At the time of the 

 discovery of the New World it was found to be one of the staples of 

 widespread agriculture from Peru northwards, but it has not been 

 found in the wild state. Its large grain is very hard, by reason of 

 the close packing of the starch-grains in the endosperm. Starch is 

 also present in the relatively large germ. Its analysis shows a rather 

 high percentage of fats ; but the hardness of the endosperm gives a 

 gritty texture to its products, and makes thorough cooking necessary. 



Rice [Oryza sativa, L.) is indigenous in India, and perhaps also in 

 China. It is a more widespread staple food than any other, supporting 

 about one-third of the human race. It has a rough husk, which 

 represents 6 per cent, of the grain, and is cleaned off before importation. 

 This tends to remove the aleurone layer also, and to carry off a pro- 

 portion of the proteids from a grain that is already deficient in them 

 (6.48 per cent.). The analysis of cleaned rice, i.e. after removal of the 

 husk, shows a very high percentage of digestible carbohydrates, with a 

 marked deficiency of proteids and fats. This justifies its use in curries 

 and puddings, in the preparation of which fats and proteids are added. 

 But as a staple food without additions it leaves much to be desired. 



