256 PROCESS OF rJEVELOPEMENT. CHAP. iv. 



and compact knot, as may be seen by truncating a 

 stem immediately above or below a small branch, 

 but particularly in the case of the Fir-tree. For 

 the branches are not formed merely by means of a 

 horizontal extension of the longitudinal tubes of the 

 trunk, but are each as it were a distinct individual, 

 of which the external cone is the trunk, and the in- 

 ternal cone the root. Hence the trunk is to the 

 branch what the soil is to the plant, the source of its 

 nourishment and stability. The branches in their 

 developement assume almost all varieties of position 

 from the reflected to the horizontal and upright ; 

 but the lower branches of trees are said to be 

 Theirposi- generally parallel to the surface of the soil on which 

 they grow, even though that surface should be the 

 sloping side of a hill owing, as it has been thought, 

 to the evolution of a greater number of buds on the 

 side that forms the obtuse angle with the soil, in 

 consequence of its being exposed to the action of a 

 greater mass of air.* 



SUBSECTION IV. 



The Bud. The Bud which in the beginning of 

 spring is so very conspicous on the trees of this 

 country as to be obvious to the most careless ob- 

 Not com- server, is by no means common to all plants, nor to 

 plants. a p' ants of all climates ; shrubs in general, and an- 

 nuals universally, are destitute of buds as well as 

 * La Nature Dcvoilec. Dialog, xiv 



