10 ROOT. 



43. The root is divided into two portions, the caudex 

 or body, and radiculte or fibres. 



44. Two modes of development are seen taking place 

 in the roots, the elongated and the spheroidal. 



45. To the first or elongated kind, all more or less 

 fibrous or cylindrical roots like those of Grasses, &c., can 

 be reduced ; and to the second or spheroidal, all such 

 roots as are seen in or approach to that of the Dahlia. 



46. The radicles are merely subdivisions of the body 

 of a root, the cellular tissue of whose extremities is 

 somewhat modified to that of the rest. It is often of a 

 greenish yellow colour, though it has been seen red, 

 and its surface is covered with numerous papillae. 



47. The radicle is an essential part of the root, and 

 its extremity has received the name of spongiole. 



48. Annual roots die away after the close of the first 

 vegetating season. 



49. Biennial roots perish at the close of the second 

 season of their producing herbage, and the first of flower 

 or fruit. 



50. Perennial roots last for many seasons, though all 

 their herbage, &c., may die every year. 



51. Cultivation of some annual roots in hot climates 

 will cause them to become perennial, and the removal 

 of perennial ones of hot climates into cold ones, cause 

 them to become annual. 



52. The root, except in what has been mentioned in 

 anatomical structure, differs little from the stem of the 

 plant ; in some, as in those where the evolution tends 

 to the spheroid, there is a very great degree of develop- 

 ment of cellular tissue. 



Stem, #c. 



53. Underground parts of plants have been called 

 roots which are really not so ; these are mere enlarge- 

 ments of the stem, or certain appendages of it answering 

 a purpose peculiarly their own. 



