THE ROOT. 5 



the root-end of the embryo, there are produced a cluster of roots at once, 

 as in the Indian corn : such are denominated fascicled roots. To this 

 class belong the grasses and very many herbaceous plants whose rapid 

 growth depends largely upon their abundant roots. 



Such are the two main forms of primary roots — that is, roots growing 

 directly from the seed ; but of course they are subject to many modifi- 

 cations. We are to consider the beet, turnip, and carrot, as presented to 

 tis in cultivation, only as exaggerated forms of tap-roots, due chiefly to 



Fig. 10.— a turnip— tap-root. 



Fig. 11. — A dahlia— thickened fascicled roots. 



natural habit but largely also to man's intelligent propagation. A some- 

 what similar exaggeration of fascicled roots is seen in the common dahlia 

 (Fig. 11). This plant starts on its course with a fascicle of roots which, 

 later on, become thickened for some distance below their junction with 

 the stem. 



As will be seen later, these various modifications of the primary forms 

 of roots have an important bearing upon plant life, and, incidentally, 

 often serve as the storehouses from which are drawn valuable medicinal 

 agents. 



In addition to the primary roots growing from the seed, nature has en- 



