54 R. H. CAMBAGE. 



they have examined, and in some cases all three have been 

 present. Out of 110 species examined, eucalyptol is given 

 as the principal constituent in 50, pinene in 31, and phel- 

 landrene in 26 species. Eucalyptol occurs in 95 of the 

 species examined, pinene in 95, and phellandrene in 36. It 

 will be convenient to refer to these oils as pinene, eucalyptol, 

 or phellandrene oils, according to which constituent pre- 

 dominates. 



The above mentioned authors have already pointed out 

 that broadly speaking the leaves having the transverse 

 venation contain a large proportion of pinene, while the 

 oblique and the parallel venation respectively indicate the 

 presence of eucalyptol and phellandrene in predominating 

 proportions. 



Pinene. — In considering the distribution in New South 

 Wales, of the typical pinene oil-yielding species, such as E. 

 corymbosa and saligna etc., it is found that the bulk of 

 them occur in the Coastal Area. The remainder are dis- 

 tributed throughout the lower Mountain Region and the 

 western parts of this State. They are practically absent 

 from altitudes exceeding 4,000 feet in latitudes south of 

 32°, an exception being found in E. rubida, which flourishes 

 at elevations up to 5,000 feet. This species, however, is 

 not regarded as one of the typical pinene oil trees, the 

 lateral veins in its leaves coming within the oblique vena- 

 tion, and its total yield of oil when tested was phenomen- 

 ally low. Pinene therefore appears to be a constituent 

 which, in the Eucalypts, has been developed amongst warm 

 rather than cold surroundings. 



In the light of our present knowledge it seems undoubted 

 that the Eucalypts have been either evolved from the 

 Angophoras, or perhaps more probably that both genera 

 have come from some common ancestor now extinct, and 

 as pinene occurs in the Angophoras, and is the principal 



