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such a stem is possibly not merely the 

 result of want of elaboration of the sap, 

 but of want of sap to elaborate ; for the 

 communication is cut off between the 

 wood, the conduit of the upward sap, and 

 the bark, the conduit of the downward 

 sap ; and even supposing the bark without 

 leaves capable of local elaboration of the 

 sap, which is very probably the case, under 

 the circumstances no sap would be supplied 

 to the bark to elaborate. Possibly^ also, 

 this is the reason why the stump ends of 

 branches or stems which have been 

 headed die down to the highest shoots. 

 I have known a decapitated beech stem lie 

 dormant for a year, that is, make this 

 slight new deposit the first summer, throw 

 out branches the second summer, and 

 continue to live. 



The descending sap in the bark of the 

 stem can, hov/ever, to a certain extent, 

 ascend in the bark of the branches, and 

 deposit new growth around them, as the 



