416 CULTIVATED VEGETABLES. 



YAM.— DIOSCOREA. 



Natural order, Sarmentacece. A genus of the 

 Dixcia Hexandria class. 



The yam appears to have been known to 

 the Romans, although it could not have been 

 cultivated in Italy, as it is said to have been 

 named Dioscorea in honour of Pedicius Dio- 

 scorides, who was physician to Antony and 

 Cleopatra, though some suppose he lived in 

 the age of Nero. He wrote a book upon 

 medicinal herbs, which is still extant. 



The Rev. G. Hughes, in his Natural His- 

 tory of Barbadoes, says, " That this very ser- 

 viceable root was formerly the peculiar growth 

 of Africa ; and the most common food of its 

 inhabitants. In all probability, it derives its 

 name from the verb yam, to eat; which is a 

 word made use of, and equally understood, 

 by all or most of the nations on the coast of 

 Guinea, though differing otherwise in their 

 language, customs, and manners." 



The yams grow wild in the woods in the 



