AND SUBORDINATION. 85 



in Fig. 1, page 31, with that of the whole branch, esti- 

 mating, in both instances, from the bud-traces marked 

 53. The age of both shoot and branch is the same, five 

 years ; yet how great the difference in the extent to which 

 development has been carried. In five years, there has 

 been no side production from the shoot, with the excep- 

 tion of a single bud, and its entire length is only four 

 inches and six lines, whilst in the same time the primary 

 axis has grown twenty-three inches and three lines, and 

 put forth two generations of shoots, one of which is fifteen 

 inches in length. 



It may be stated as a general rule, that, in very favorable 

 conditions, verypowerfully growing branches will put forth 

 as many as four or five generations of side-shoots, but 

 the vegetative power here expires, and the last generation 

 of shoots are entirely rudimentary, appearing as mere 

 rosettes or clusters of leaves, no intervals of stem what- 

 ever being formed between them. 



Hence, the power of a branch to give forth branehlets 

 is not indefinite, but diminishes with each succeeding gene- 

 ration, until the vegetative power ultimately arrives at a 

 minimum. A single glance at the branches of a tree is 

 all that is necessary to satisfy the reader that there is a 

 retarded growth in length and thickness of each succes- 

 sive generation of shoots or branehlets. And this remis- 

 sion of growth is not founded on a difference of age 

 between the branch and branchlet, nor on a cessation of 

 growth at a certain stage of the same, for all axes, so long 

 as they continue to live, grow forth indefinitely ; but this 

 circumspection of growth is rather founded on a difference 

 in the intensity of growth from the commencement, on a 

 positive loss of vegetative energy. 



When, therefore, the growth of the axis becomes com- 

 pound, other considerations must enter into our calcula- 

 tions with reference to the development of any individual 

 axis, such as its relative position on' the primary axis, or 

 in regard to the number of successive generations. If it 

 occupies an inferior and subordinate position on the pri- 

 mary axis, or in the chain of successive generations, its 

 growth will be necessarily very limited. ^ 



