404 



CONSERVATIVE ORGANS. 



[LECT. vin. 



the last independent ligneous zone of the branch, 

 and e. that of the trunk : but it must be re- 

 marked that the other zones, common to both, 

 are the result of alburnous matter furnished by 

 each in particular. 



A very clear idea of the origin and connexion 



of branches may be ob- 

 tained by the aid of a 

 diagram, similar to one 

 which was employed by 

 Du Hamel to illustrate 

 the opinion he entertain- 

 ed, although that was 

 directly opposite to the 

 theory I have advanced. 

 Let us imagine the fi- 

 gure in the margin to 

 be a tree four years old ; 

 the cone a. representing 

 the first year's growth, 

 fc. b. the second, c. c. the 

 third, and d. d. the fourth. The buds furnish- 

 ing the branches e.f. g. h, are all generated on the 

 surface of a. in the spring of the first year ; but in 

 that year e only sprouts into a branch; on the 

 surface of which is generated i. } which in its turn 

 generates k. In this series, each branch has sprung 

 in regular succession from that of the former year ; 

 the age of the branch being marked by the num- 



"bed 



