CROP-PLANTS 345 



PULSE CROPS 



In addition to the pulses mentioned on page 339, Vigfia unguicu- 

 lafa, Voandzeia subterranea, Kerstingiella geocarpa^ Cajanus cajan, and 

 the introduced Phaseolus aureus, certain other crops are important. 

 Dolichos lablab is confined to East Africa, from the Sudan to 

 Nyasaland. Many varieties o{ Phaseolus lunatus, an American species, 

 are grown in West Africa and it is occasionally seen in East Africa. 

 Another American species, Phaseolus vulgaris, is cultivated in the 

 cold season in East Africa in many varieties. Mucuna aterrima and 

 allied species are grown in the Rhodesias, Nyasaland, and Tan- 

 ganyika. This crop is regarded mainly as a food for times of 

 scarcity owing to the poisonous property of its seeds, which entail 

 boiling in many changes of water. The sword-bean [Canavalia en- 

 siformis) occurs wild, and to a small extent cultivated, in West 

 Africa. A study of V. unguiculata, on lines similar to those adopted 

 in the case of sorghum, has been commenced by Kew in co-opera- 

 tion with the agricultural departments of the various British 

 tropical dependencies. 



The importance of pulses as an element of native diet, particu- 

 larly in areas where they are the principal source of proteins, is 

 now widely recognized, and in those territories where scales of 

 rations for native labour are prescribed by law it is usual to include 

 a fixed quantity of pulses. The increasing interest which has 

 recently been taken in the nutritional problems of colonial peoples 

 may lead to the further development of research on these impor- 

 tant crops. 



FODDER CROPS 



Lucerne {Medicago sativa) is one of the best-known forage crops 

 and is grown throughout temperate parts of the world. In South 

 Africa a considerable area, amounting to nearly 100,000 morgen, 

 is under lucerne, and Professor Leppan (1924) has written an 

 exhaustive treatise on its cultivation there. More recently the 

 Union department of agriculture has published a study of this 

 crop (Tarpin and McKellar 1936). Lucerne has been found to 

 have high nutritive value as food for human beings as well as for 

 stock. Fox and Wilson (1935) point out that it is remarkably rich 

 in vitamin C, in addition to containing a considerable amount of 



