16 The Garden. 



of tMs substance, the root or radicle, at first a mere rounded 

 cone, extends and pierces the earth in search of food, while 

 the other extremity elongates in the opposite direction, bringing 

 the cotyledons^ or seed-leaves (except when these remain per- 

 manently in the ground, as in the pea, wheat, rye, etc.), and 

 the rudimentary leaves and stem, to the surface of the soil. 

 The process of germination is now completed — the plant is 

 born. 



II.— THE BOOT. 



The root, the stem, and the leaves are called the fundamental 

 organs of plants. Of them vegetables essentially consist ; and 

 the various organs known by other names are really but repeti- 

 tions, under more or less modified forms, of these essential parts. 



Germination, as we have seen, pushes the root downward 

 into the earth, where, extending ly the addition of new matter 

 to its pointy it soon enters upon the exercise of its function — 

 the absorption of the crude food- of the plant from the soil. 

 This is carried up through the stem into the leaves, to be di- 

 gested or assimilated, and returned to the stem and root, and 

 used in the formation of new branches, leaves, and rootlets, as 

 well as for increasing the length and size of those already 

 formed. The more a plant grows, therefore, the more are the 

 means of growth multiplied. 



As the roots are extended by the addition of new matter to 

 the extreme points, these points are exceedingly delicate and 

 easily injured. It is mainly through them^ too^ that absorption 

 tal^es place. It is readily seen, therefore, why the careless or 

 unskillful removal of plants from the earth, for the purpose of 

 transplanting, by destroying the delicate points of the roots, or 

 spongelets^ as they are called, always checks so greatly their 

 growth, and often destroys their life. 



Their peculiar mode of growth admirably adapt roots to 

 pierce the earth and insinuate themselves into the minutest 

 crevices. Thus they pass on from place to place in search of 

 fresh pasturage, shifting their mouths, although their bodies 

 remain stationary. 



