1908.] Phaseolus Lunatus Beans. 



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in India to be poisonous under some circumstances. Other 

 vernacular names in use for these beans are " Lima " and 

 " Duffin," the former being in common use in the United States. 



In view of the fact that the white Rangoon beans examined 

 at the Imperial Institute yielded no prussic acid, attempts 

 were made to obtain the white beans of Phaseolus lunatus 

 grown in other localities than India for comparison with them, 

 and eventually " Haricots de Lima," grown in the South of 

 France, were obtained through a firm of seedsmen in Paris. 

 These were much larger than either the Mauritius or Indian 

 beans and were cream white in colour. They were examined 

 and found to furnish no prussic acid. 



These observations that the red Rangoon beans yielded traces 

 of prussic acid, and the white beans from two different sources 

 none, confirmed the statements recorded by various authors 

 that the white beans of Phaseolus lunatus are safer than the 

 red kinds. Thus Professor Church, in his " Food Grains of 

 India " (p. 155), says : — " This is one of the species of Phaseolus 

 which sometimes exhibits marked poisonous properties. It 

 is desirable that great care should be taken in selecting for 

 cultivation the best variety of Lima beans. The large oval 

 white seeded kinds, with at most a brown or black mark close 

 to the hilum, are preferable to those with flattened reniform 

 seeds having blotches of red or veinings of black." 



On this point it is of interest to note that Cordemoy has 

 stated (" Flore de File de la Reunion," 1895, p. 389) that in the 

 wild state the beans of Phaseolus lunatus are purple and very 

 poisonous ; that on cultivation the colour of the seed becomes 

 modified to a yellowish tint with stripes or violet splotches, and 

 that in this state the beans are rarely poisonous ; and lastly 

 that, after prolonged cultivation, large white beans are pro- 

 duced which are harmless. This statement, taken in con- 

 junction with the facts recorded above, seemed to indicate that 

 by cultivation of the plant the beans become white and then no 

 longer produce the glucoside capable of yielding prussic acid. 



After carefully reviewing the facts in consultation with the 

 Director of the Imperial Institute, the Board of Agriculture 

 came to the conclusion that it was desirable at this stage to 

 warn consumers against the use of red and dark coloured beans 

 of Phaseolus lunatus. (Journal, December, 1902, p. 373.) 



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