126 H. G. SMITH. 



of hydrobromic acid, it is probably to the formation first of this 

 acid that the colour given with bromine is due. Hydrochloric acid 

 gives the same colours, but the reaction is slower. 



In a solution prepared as above, sulphuric acid gives a crimson 

 colour at once, soon changing to a purplish colour. Phosphoric 

 acid in the same manner gives first a pink then a crimson and 

 finally a violet colour. These colour reactions are exceedingly 

 delicate. 



The evidence so far obtained show this sesquiterpene to have 

 been previously undetermined. It is proposed to give it the 

 name Aromadendrene utilising Dr. Andrews' name for the genus. 



I am indebted to my colleague, Mr. R. T. Baker, f.l.s., for 

 the botanical determination of the species which provided the 

 material. 



