THE INNER BARK. 83 



The first or outermost is formed of sets, or bundles 

 of vessels, at first straight and mutually parallel, but 

 afterwards separating, except at a few points, as is 

 beautifully seen in the lace tree ; where they resemble 

 woven cloth, or rather very regular lace work. 



In the fresh shoots of trees, which are produced 

 yearly, only a single ring of vessels is observable, 

 which then constitutes this layer, before there is any 

 other formed. 



Vessels of the Bark. Slice from a plant, greatly magnified. 

 a, bark ; b, b, rings of vessels ; c c, pulp bark, with its cells ; 

 d, the wood. 



Within this a fresh layer of similar net- work ves- 

 sels is formed, while the former becomes more hard 

 and firm. In the same manner additional layers are 

 formed, and the whole series of these, excepting the 

 outer one, is considered the second coat l of the inner 

 bark. 



(1) In Latin, Liber, which is not very appropriate in most cases. 

 G 2 



