70 COMPOUND ORGANS OF PLANTS. 



a perfect state, become abortive or incompletely developed. It 

 is in fact almost always the inferior buds which are thus reduced 

 to a rudimentary condition. The light does not get access to 

 them so freely as to the buds towards the summit of the 

 branches, and hence the lower part of the branches is generally 

 naked and deprived of branchlets. The symmetrical arrange- 

 ment of the branches with the leaves is also prevented. 



By the growth of adventitious or irregular buds, that is to say, 

 of buds which come in parts of the stem, between the leaves, and 

 not in their place in the axils of the leaves. Sometimes, owing 

 to the growth of the leading buds, the growth of the latent 

 axillary buds is checked altogether, in which case they sink 

 beneath the surface of the stem, and are buried beneath the 

 succeeding layers of wood ; but their vitality is not destroyed 

 so long as they remain at a certain depth in the stem, that is 

 to say, in the alburnum or sap-wood. The trunks and branches 

 of trees, therefore, always contain an immense number of these 

 buried buds, and should some of the leading branches be broken 

 off by high winds, or sustain injuries from other causes of this 

 character, then the flow of sap to them becomes so powerful 

 that they will force their way through the wood to the surface, 

 although that wood be the successive growths of years, and 

 break forth into branches. All must be familiar with the 

 sight of willows and other trees, whose main branches have 

 been thus- broken, and -whose trunks have, nevertheless, been 

 covered with young branches and shoots, the growth of buds 

 which "have been buried in their wood, and for years dormant 

 beneath their surface. 



From these facts it is plain that those forms of life which we 

 call plants, although rooted to the soil, and more exposed by 

 this circumstance than any other living being, are nevertheless 



