XII. 



CROPS 



241 



(b) Leguminous Seeds. The Uguminosce differ from the cereals 

 in containing much more nitrogenous matter and lime and in b^ing 

 poorer in silica and phosphoric acid. 



The principal leguminous crops grown for the sake of their seed in 

 Britain are beans and peas, but in warmer countries many other legumes 

 are available. 



Field Beans (Viciafaba) generally do best on heavy lands, being 

 sometimes planted in the autumn (winter beans) but often in the 

 spring. 



Many species of leguminous plants are known as " beans " the 

 chief varieties grown as farm crops (chieHy in tropical or subtropical 

 climates) being Phaseolus vulgar is, kidney or haricot beans ; P. 

 lunatus, Lima or Java beans ; P. radiatus, Adzuki beans ; Glycine 

 hispida, Soy or Soja beans ; Mucuna utilis. velvet beans. 



All beans are rich in protein and form valuable, concentrated 

 foods for men and animals. The occurrence of a poisonous cyanogenetic 

 glucoside in Lima beans has already been referred to (vide p. 215). 



The Pea. The field pea (Pisum arvensis), the garden pea, P. 

 sativus, and the edible-podded pea, P. macro-carpus, are the chief 

 species, of which there are many varieties. 



The soil for peas should be rich in lime, but not too rich in 

 nitrogen, otherwise the yield of seed is small. 



The "Chick Pea' r (0icer arietinum) or " gram" of India fur- 

 nishes a seed which may be used as food. The crop is well adapted 

 for dry hot climates. The haulms, however, are of little use as 

 forage. 



"Cow Pea" (Vigna catjang or Dolichos sinensis) rather resembles 

 a bean than a pea. The seed may be used as food, or the whole 

 plant, cut before the seed is ripe, forms a most nutritious hay, greatly 

 relished by stock. The plant withstands drought very well and 

 attains maturity rapidly. 



"Pea Nuts," "Ground Nuts," or "Monkey Nuts" (Arachis 

 hypogcea) grow well in hot countries. After flowering, the stalk 

 bends over and enters the soil, beneath which the seeds ripen. In 

 harvesting, the crop is ploughed up and the plant and pods forked 

 out. Several varieties are known, some with two, others with three 



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