Nature^ Longevity ^ and Size of Trees, 13 



cease to be, and never afterwards become, the seat of any 

 vital action. 



I. First, then, the annual growths emanating from the 

 buds constitute, severally, perfect and independent plants ; 

 and a succession of such plants may be kept up from year to 

 year, for ever, from buds alone. 



On the return of spring, " when the earth, by an annual 

 miracle, rises again, as from her grave, into life and beauty,'* 

 we see the buds on each of the stems of the previous year, 

 first swelling, and afterwards sending out an entirely new 

 stem, new leaves, flowers, and buds, all of which are per- 

 vaded and connected together by a new set of circulating 

 vessels or cells. And in the course of the season seed forms 

 and is matured. Now, in this annual formation, we have 

 issuing from the buds on the stems of last year all the parts 

 essential to the constitution of a perfect plant ; and on the 

 new stem of this year we have buds provided for the evolu- 

 tion of such a plant next year. 



With the view of shewing more distinctly, at once the in- 

 dividuality and the independency of the growths thus formed, 

 and their claim to be regarded as perfect plants, and the 

 ability of each of them to reproduce its kind annually in end- 

 less perpetuity from buds, reference may, in the first in- 

 stance, be made to what obtains in the potato-plant — a plant 

 which, though not a tree, contains all the elements of one, 

 and is equally perennial in its duration as any tree. The 

 tuber familiarly known as the potato bears an exact resem- 

 blance to, and is essentially of the same nature with, the 

 yearly shoot or stem of a tree. It is, in fact, an underground 

 stem, consisting of a layer of bark, and a layer of woody 

 tissue, enclosing a mass of pith, and furnished with buds. 

 This underground stem, when planted in spring, sends out 

 from each of its buds a growth which has a stem (under- 

 ground), and leaves and flowers, and forms buds and seed, 

 structures which are exact counterparts of those composing 

 the growths issuing from the buds of trees. Does any one 

 doubt that the annual potato-growths constitute perfect and 



