ORIGIN OF BUDS. 147 



floated in the sap : for on no other principle could 

 he account for their inexplicable appearance. There 

 are many trees having- a fine smooth trunk from 

 which not a spray would be put forth while its 

 branched head remained alive : but on being- decapi- 

 tated thousands of shoots would issue from the bole, 

 even if its pith, and almost all its body of timber 

 had g-one to decay ; a strong proof that the envelope 

 contains the rudiments or principles capable of being 

 resolved into buds as well as of radicle fibres. 



It has been supposed by some physiologists, that 

 the medullary rays are the tracts of buds, and that 

 all buds originate on, or proceed from the pith ; but 

 we have no certain evidence of the truth of these 

 ideas ; on the contrary we find, that buds of many 

 kinds of trees issue from roots where pith has never 

 existed; and medullary rays, or partitions rather, 

 are abundant where no buds are ever or can possibly 

 be produced, viz. on the internodes of jointed stems ; 

 example, the grape vine. And it may be further 

 observed, that in the plant just named the greatest 

 number of shoots, in fact every shoot, is ejected 

 from the articulations where the pith is visibly 

 interrupted. Of what are called medullary rays, we 

 may observe further, that though known by this 

 name, they do not all take their rise from the pith ; 

 as the stem increases in diameter, intermediate par- 

 titions come into existence at different distances 

 from the centre, and appear to originate in the 

 bark rather than in the pith. 



L 2 



