INDIAN CORN. 149 



is due to difference in compactness of the starch 

 grains, just as the more compact crystals of ice pro- 

 duce a glossy appearance, while the crystals of snow, 

 being less compact and containing more air, more 

 perfectly reflect the light, and thus produce a white 

 appearance. 



Dr. Sturtevant first pointed out the relation between 

 the interior arrangement of the kernels and the types 

 of corn, which he called agricultural species, and gave 

 Latin names to them. He has not been followed by 

 other writers. 



The types of corn are as follows : 



1. Dent corn is that type in which the split kernel 

 shows the germ, the glossy starch on each side and 

 the white starch extending to the top of the ker- 

 nel. The kernel is indented on the top, evidently 

 because the softer starch shrinks in the center, while 

 the denser starch on the sides holds the sides in a 

 straight line. The kernels of dent corn are more or 

 less wedge-shaped. 



2. Flint corn is that type in which the split kernel 

 shows the germ, the white starch and the glossy 

 starch surrounding. The surrounding dense starch 

 prevents the kernels from indenting. The kernels 

 are hard, smooth and more or less oval. 



3. Pop corn is that type in which all, or almost all, 

 the endosperm or starch is glossy. The kernel is 

 an elongated oval in outline and extremely hard. 



4. Soft corn is that type in which the endosperm 

 is entirely white. The shape of the kernel is similar 

 to that of the flint corn, and the starch grains in the 

 endospcriii being loosely arranged the kernel is easily 

 crushed. 



