leaf-sheaths, coarse seminal roots and susceptibility to 
lodging and smut—hybridized with a species of 'Tripsa- 
cum to produce the new genus Euchlaena and new varie- 
ties of maize exhibiting Tripsacum admixture. 
7. Western Guatemala is thus regarded as a secondary 
center of origin of cultivated maize varieties. 
8. ‘The potential value for purposes of plant breeding 
of the Tripsacoid varieties of maize of Guatemala is 
pointed out. 
[ 248 ] 
