38 TRANSACTIONS AND I'KOCEEDINGS OF THK [Sess. lxv. 



camhiwn." This is the first protest published against the 

 erroneous definition of bark. 



In 1898, Vines issued his "Elementary Text-Book" 

 (22), and, at p. 153, referring to everything outside the 

 phellogen, says — " These dried-up tissues, which may 

 belong to different tissue-systems, and include the most 

 various forms of cells, constitute what is known as hark." 



In the same year Strasburger's " Text- Book of Botany " 

 (23) appeared, and gave a similar definition to the preceding. 



In 1900, B. D. Jackson (24) defined bark as — (1) "The 

 outer integuments of the wood, and exterior to it; all 

 tissues outside the cambium"; (2) "frequently restricted 

 to the periderm, and tissues external to it." 



See also L. H. Bailey's " Botany " (25, p. 265), published 

 in 1900. It adheres to the old English definition. 



Evidence enough has been produced to show that there 

 is inconsistency in the use of botanical terms, as they 

 are applied to that region of a secondary axis which lies 

 outside the wood ; there is also direct contradiction in 

 the two definitions of bark, and this confusion of terms 

 demands a readjustment. 



It may be said that most botanists now follow van 

 Tieghem in recognising epidermis, cortex, and central 

 cylinder in the primary axis of the Spermaphyte. 



Cortex, therefore, has lost its position as the synonym 

 of rind or bark. 



Since Rinde, in German, and bark, in English, are un- 

 doubtedly synonymous, it remains to recognise two regions 

 in this bark ; outside of the phellogen is the " dead bark," 

 and between the phellogen and cambium the " living bark." 

 Should there be any difficulty in such a distinction, on the 

 ground that some of the elements of the inner bark are 

 already dead, and that a layer or two of cells outside the 

 phellogen are still alive, then let us speak of the " inner 

 bark " and the " outer bark," with the phellogen layer as 

 the boundary line between them. 



The proposed terms have been used by various writers, 

 so that they cannot be objected to as new or additional 

 names ; they are consistent with the facts of the case, and 

 we have already the analogy of the division of wood into 

 heart-wood and sap-wood. 



