Bui. 180, Bureau of Plant Industry, U. S. Dept. of Agriculture. 



Plate VI 



Fig. 1.— Spikelet of Triticum monococcum, Showing the Characteristic Secondary 

 Tooth of the Glume. Fig. 2.— Spikelet of Triticum dicoccum dicoccoides, Show- 

 ing the Secondary Tooth, as in T. monococcum. Fig. 3.— Spikelet of Triticum 



DICOCCUM DICOCCOIDES, SHOWING THE ABSENCE OF THE SECONDARY TOOTH OF THE GLUME. 



(All enlarged 4 diameters.) 



