156 Field, Forest, and Wayside Flowers 



For if such vegetable friends are wantonly re- 

 moved, or are allowed to perish, valuable tracts of 

 ground are buried under sand, or are altogether 

 washed away, and harbors are rendered unsafe by 

 accumulating shoals and bars of sand or mud, 

 brought from other shores. 



Some species of grass, in the course of many 

 summers, convert marshes and half-submerged 

 shores into firm land, and hence have been called 

 "Nature's most valuable colonists." 



They hold territory which has been wrested from 

 the waters, and which, but for them, would speedily 

 be retaken. 



Thus they fix, if they do not change, the 

 bounds of land and sea, and help to make geog- 

 raphy for the boys and girls of coming generations. 



To the evolutionary botanist the grasses are pe- 

 culiarly interesting, for while many of their charac- 

 teristics show the highest possible adaptation to 

 the conditions of their lives, their flowers are con- 

 spicuous instances of degeneration. 



They have reached, it seems, the last stage in a 

 strange, eventful history. It is surmised that the 

 first flowers ever born into the young world had 

 stamens only, or a pistil only, as the case might 

 be, had neither calyx nor corolla, and were wind- 



