VXD THEIR ESSENTIAL OILS. 143 



The pale-coloured hardwood timbers of Tasmania are 

 excellent, and have long occupied a front position in the 

 world's timber markets, but there is one feature worthy 

 of notice, and that is the utilisation of some of 

 these for cabinet work, such as I'J . ohliqua and 7C . Dele- 

 gate^isis as " Tasmanian Oak." To these might be added 

 the timber of A'. Kodwdi/i, which appears to be of equal 

 excellence in this connection. 



Species Yielding Commercial Timbers. 

 Gums — , 



K. acervula (Red Gum). 

 E. globulus (Blue Gum). 

 E. Gunnii (Cider Gum). 

 E. linearis (White Peppermint), 

 E. viiniualis (Manna Gum). 

 E. Muelleri (Brown Gum). 

 fj . Delegatensis (Gum-topped Stringy-bark 

 or Tasmanian Oak). 



Stringy-barks — 



E. ohliqua (Stringy-bark). 



Hard, Furrowed, Compact Barks — 

 E. virgata (I^onbark). 

 E. Rodwayi (Black Gum). 

 E . taeniola. 



Peppermint — 



E. ami/gdalina (Black Peppermint). 



The evidence now brought forward in this paper respect- 

 ing the affinities and differences between the Tasmanian 

 Eucalypts and identical species or allied forms growing on 

 the mainland appears to further emphasise the evolution- 

 ary differentiation of the various species, first brought for- 

 ward in our work on the Eucalypts published in 1902. 



Variation in altitude and climatic conditions, the 

 result of considerable earth-movement, would naturally 

 force the species thus separated to endeavour to overcome 

 this interference, and to adapt themselves to these new 

 conditions. This environmental' change would thus tend 

 to establish new features and constituents. 



For instance, the affinity existing between E. amygda- 

 lina of Tasmania and the form of E . amygdalina growing 

 on the mainland is evidently close, yet they are not now 

 identical species, in the present acceptation of such, either 

 botanically or chemically, and the divergence has gone 

 sufficiently far for specific differences to be observed. 



