lo Feb., 1913. 



W/ieat and its Cultivation. 



99 



during the time it is seeking to establish itself in the soil. The endosperm 

 occupies, on an average, about 80 per cent, of the kernel. It is prin- 

 cipally compcsed of what are known as starch cells — large elongated cells 

 with their long diameters arranged radially to the surface of the kernel. 

 These starch cells, however, are found, on examination, to con.si.si of an 



Cellular ileurcrt 



tissue Elifssperm cells Tesfi fnfoarfi fpie>rp .7; 



Photo.] IC. C Brittlpbank 



FIG. 3. LONGITUDINAL SECTION OF A GRAIN OF WHEAT SHOWING THE 



INTERNAL STRUCTURE. 



outer covering of cellulo.se containing within a large number of starch 

 grains. Besides these starch grains, the starch cells contain a consider- 

 able amount of gluten, and Fleurent has shown that the amount of such 

 gluten varies with the position of the starch cell in the endosperm. From 

 a detailed examinarion of a number of Inrlian. Russian, and French 



Photo.] S- C. Bntrl.-i.aiik. 



FIG. 4. LONGITUDINAL SECTION OF FEDERATION WHEAT. 



wheats, he was able to show that the amount of gluten in the endosperm 

 increased from the centre to the periphery. In an Indian variety, e.g.. 

 the amount of gluten varied from 8 per cent, at the centre to \o\ per 

 cent, at the peripheral portion of the endosperm. 



It is the endosperm which forms the tlour in thr process of milling the 

 grain. 



