THE WHEAT CULTTJEIST. 



27 



y b 



Fig. 3. — A kernel of 

 wheat magnified. 



wheat with the groove downward. The part marked 

 ^represents the main part of the kernel which supplies 

 nourishment to the growing plant. 

 By cutting a kernel of grain into thin 

 slices with a sharp knife, the germ or 

 embryo may be seen at e. At b the 

 plumule, or stem, appears ; and c rep- 

 resents the radicle, while A and ^ 

 show the first and second skin of the 

 kernel. The true roots issue at the 

 points of the kernel represented at 

 f and g. J. H. Klippart states in his 

 " Wheat Plant," that as soon as moist- 

 ure has found its way through the 

 canals in the husks or skins, a, a, 5, c, 

 and d, so as to be in contact with the 

 starch cells, e, the moisture penetrates the cell-walls 

 of the seed and its embryo, and there forms a strong 

 solution. The seed has now the power of decompos- 

 ing water. The oxygen in the water combines with 

 some of the carbon of the seed, when the product is ex- 

 pelled as carbonic acid. The presence of moisture and 

 oxygen induces putrefaction of a portion of the albu- 

 minous matter in the cells, which becomes an actual fer- 

 ment, exhaling carbonic acid gas, generating heat, and 

 converting the insoluble starch which is stored up in the 

 kernel into soluble -sugar. 



The starchy substances deposited within the seed were 

 undoubtedly designed to furnish food to the young plant 

 until the roots and leaves have attained sufficient size to 

 derive nourishment from the soil and the atmosphere. 

 In wheat, starch is the most important ingredient of 

 plant food. 



