THE ROOT. 



a 



the root-end of the embiyo, the? arc pvoiluccd a chi ^ter of roots at once, 

 as in the Intliiiii ccn-n : such are ;nniiuiiat('il fascicled roots. T(j this 

 class belong tiie grasses ami very many licrbaceuiis plants whose rapid 

 growth depends largely upon their abundant roots. 



Such are the two main forms of primary roots — that is, roots gi'owing 

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

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

 us in cultivation, only as exaggerated forms of tap-roots, due chitlly to 



rmmm X 



\ 



Fig. 10. — A turnip— tap-root. 



Fio. 11.— A ilnhlia— thickened fascicled roots. 



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

 what similar exaggeration of fascicled roots is seen in tlio 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 sei-ve as the storehouses from which are drawn valuable medicinal 

 agents. 



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



