50 



LETTERS ON TREES. 



of dead leaves is a bud — a truncate flesh-like substance, 

 resembling the root-plate of a bulb, but of nearly the 

 full size of the after-diameter of the tree on the sum- 

 mit of which it rests. This bud, formed by the plant of 

 the previous year, and consisting mostly of a mass of 

 cellular tissue, first sends out from its exterior a tuft of 

 fresh leaves, and then extends itself a short way hori- 

 zontally. Next, it rises slowly upwards, leaving the tuft 

 of leaves at its base, but giving off others in succession 

 from its sides and summit. The leaves in their turn 

 send down bundles of woody tissue, which traverse 

 the cellular tissue, and, proceeding some distance down 

 the tree, finally curve outwards, and lose themselves 

 in the cortical integument of its trunk, immediately 

 within which (contrary to what obtains in the Exogen) 

 the most compact wood is always found. These 

 bundles are the roots of the plants ; and these, together 

 with the cellular tissue and the persistent remains of 



the first set of leaves (which decay 

 and drop off in the course of the 

 season), are all that can be re- 

 garded as the stem of the plant, 

 — for, in reality, according to 

 Botanists, it has no proper stem. 

 And this stem, such as it is, to- 

 gether with those of the plants of 

 former years, constitute the trimk of the Palm-tree. 

 In figure 8 is represented a transverse section of this 



