36 TKANSACTIONS ANl) I'K(JGEKIJL\G.S OF TJIK [Sess. Lxv. 



and the fifth edition of Bentley's "Manual" (16) appeared. 

 The definition of " bark " in the former is — " The rind or 

 cortical portion of a stem, especially of an exogen "; in 

 the latter — " The bark is situated on the outside of the 

 stem, surrounding the wood, to which it is organically 

 connected by means of the medullary rays and the cam- 

 bium layer." These definitions are correct, but Bentley 

 uses cortex as a synonym of bark. Such a use of cortex 

 is not in keeping with modern terminology, although, 

 as noted above, the two terms were at one time 

 synonymous. 



In 1888, the second edition of Bower's "Practical 

 Botany" (17, pp. 115, 116) was published, and the 

 following shows that he still adhered to his conjoint 

 translation of 1884: — "As stems grow older, layers of 

 cork appear successively farther and farther from the 

 external surface : not only the cortex, but also the outer 

 and older portions of the phloem are thus cut off from 

 physiological connection with the inner tissue : the term 

 hark is applied to tissues thus cut off, together with the 

 cork which forms the physiological boundary." 



In 1889, Marshall Ward' published "Timber" (18). 

 At p. 2 — " This log of wood, with its annual rings and 

 medullary rays is clothed by a sort of jacket, consisting of 

 cork and softer tissues, and termed the cortex, or, more 

 popularly, the ' bark ' (an unfortunate word, which has 

 caused much trouble in its time)." At p. 199 — "It will 

 be remembered that our typical log of timber was clothed 

 in a sort of jacket, termed the cortex, the outer parts of 

 which constitute what is generally known as bark. This 

 cortical covering is separated from the wood proper by the 

 cambium." At p. 206 — "Some of these refer to the 

 anatomy of the various ' liarks ' — the word ' bark ' being 

 commonly used in commerce to mean the whole of the 

 cortical jacket, — the places of origin of the cork layer, 

 and the way in which the true bark peels off." Finally, 

 at p. 208, he says — "We have also seen that the cam- 

 bium is not the only living tissue below the bark : the 

 cortical parenchyma, and the cells of the inner cortex 

 (technically, the phloem) are all living and capable of 

 growth and division." 



