432 The Rev. P. Keith on the Origin of Buds. 



buds lodged in the embryo plant, or protruding from the sur- 

 face of the shoot, and the new formed bud, or rudiment of a 

 bud, a minute, and insulated, and imperceptible globule or fila- 

 ment ; there is nothing incredible in the supposition of its being 

 carried upwards with the current of the ascending sap in its 

 passage through the alburnum ; or, of its entering even the 

 plexus of the vessels of the inner bark, being again carried 

 downwards with the current of the descending and proper 

 juice, as well as ultimately deposited in a situation favourable 

 to its future evolution. The necessity of accounting for the 

 appearance of the bud and shoot that originated in the lip of 

 the closing wound of the Elm-tree, — that is, in a new layer of 

 alburnum that was spreading over the surface of an old and 

 dead layer, — renders the adoption of this or of some such hy- 

 pothesis indispensable. Not that the horizontal progression of 

 the bud as a general rule is to be denied. The fact is esta- 

 blished beyond a doubt. But that the exception to the rule 

 must be accounted for also ; and even upon the principle of the 

 rule itself, I am not sure that the longitudinal progression of the 

 bud may not be occasionally wanted, if it were but to bring buds 

 up to the point of their horizontal protrusion. 



If we admit the above process in the shoot of the first year, 

 we shall have no difficulty in extending it to the shoots of future 

 and succeeding years. The buds crowning the primary shoot or 

 distributed over its surface, will evolve and develope their parts 

 in the manner of the bud of the embryo plant ; and the buds of 

 future shoots, in the manner of those of the primary shoot ; so 

 that the growth of the primary shoot is an epitome of the growth 

 of the whole plant ; and that which illustrates the one will illus- 

 trate also the other. There may be error in our inferences : but 

 if the microscopic observations, to which I have already alluded, 

 are good for anything, we must believe that buds do actually 



ascend 



