1 68 Field, Forest, and Wayside Flowers 



Just inside the innermost skin of the wheat- 

 grain there is a layer of nitrogenous substance, far 

 richer in nutriment than the starchy sub- 

 stances which lie beneath it. When the 

 integuments of the wheat-grain are torn 

 off, this nutritive "aleurone" layer is apt 

 to come away with them. But any proc- 

 ess of milling which can keep the 

 aleurone with the starchy inner part of 

 the grain will produce a flour highly nu- 

 FIG. 42. tritive in proportion to its bulk. 



Caryop- 



sis of the The parts of the grasses are simple and 



wheat. 



( F r 5 OI the few but Nature can so vary their forms 



Vegetable J 



and their arrangement that botanists rec- 

 ognize about four thousand species, of which over 

 two hundred and sixty grow east of the Rockies. 



The number of flowers in each spikelet varies 

 greatly in different species. Sometimes there are 

 a dozen or more sometimes there is but one, 

 with rudiments and traces of others above it. 

 The spikelets may be ranged down one side of 

 a main axis in compact, straight rows; they 

 may surround the axis, as they do in " timothy " 

 grass, forming a cylinder of bloom, or they may 

 dangle, as the oat-spikelets do, at the tips of 

 slender branchlets, which form part of larger sprays. 



