CHAP. I. THE ROOT. 41 



annually;* being originally protruded in the 

 spring, perishing in the winter, and again succeeded 

 by a new set in the spring following. Hence they 

 seem to bear the same relation to the root that the 

 leaves bear to the stem or branch. 



If roots are viewed with regard to their direction The direc- 

 as penetrating the soil, some will be found to de- tu 

 scend perpendicularly, others obliquely, and others 

 to extend themselves in a direction parallel to the 

 horizon. 



If viewed with regard to their surface they are 

 marked with scars or inequalities ; or covered with 

 scales, or beset with a fine down, or with soft and 

 fine hairs, 



If viewed with regard to their substance they are Substance, 

 milky, as in Sonchus arvensis, or Corn Sow-thistle ; 

 or fleshy, as in Tamus communis or Black Briony ; 

 or woody, as in the roots of shrubs and trees. 



The colour of the root is generally darkish ; Colour, 

 though in some plants it is white, as in Horse-ra- 

 dish ; in some yellow, as in Broad-leaved Dock ; and 

 in some red, as in the Carrot. 



The odour of the root is often one of its most Odour, 

 distinguished properties ; being sometimes strong 

 and ungrateful, as in Wild Valerian ; sometimes pun- 

 gent and penetrating, as in Horse-radish ; and 

 sometimes spicy and aromatic,, as in Spignel and 

 Sweet Cicely. In Pucedanum officinale,it resembles 

 that of sulphur. 



* Physique dcs Arbres, liv. i. chap. v. 



