16 



the starch grains. The spemiodcrm or inner covering of the seed 

 is yellowish is color and made up of three layers, the outer epider- 

 mis being made up of wavy-walled rectangular cells of varying 

 size. Under this is found a second layer of spongy parench^ona, 

 the cells of which are very irregular in both size and shape, and 

 between which are found a great many circular intercellular 

 spaces. The cell content is yellowish or greenish in color. This 

 layer is characteristic of buckw^heat. 



The grains of buckwheat starch are either sharply polygonal 

 or sphaero-polygonal with one or more facets, and range in size 

 from 5 — VIjjL in diameter. Angular or rod-like aggregates are 

 often present but large oval aggregates are never found. Occasion- 

 ally an isolated, angular cell of the starch parench\Tna will be found 

 in which the grains entirely fill the cell. After treatment with 

 alkali the starch cells show a network of homogenous threads 

 throughout the cell. Fig. S shows the elements of buckwheat 

 mentioned above. 



KAFFIR CORN. 



(Andropogon Sorghum, Brot.) 



Several varieties of sorghum have been grown in the past, 

 and now the grain is becoming more important as a food for 

 stock and other farm animals. It is often found also in chicken 

 feeds, in a more or less coarsely ground condition. When found 

 finely ground, the glumes removed, it is very difficult to disting- 

 uish it from com meal, as the starch grains of Kaffir corn 



Fig. 9. Kaffir Corn. 



show practically no differences in structure from those of 

 maize. As a rule, however, the glumes adhere somewhat to 

 the grain, and as they are in color reddish brown to almost black, 

 one can usually find fragments by which the product can be iden- 

 tified. The glumes also tend to darken the ground product. 

 When coarsely ground the pieces are rather easy to identify on 

 account of the color and shape of the grain. The whole grain is 



