purified crystallised eudesmo] to slowly change its character, until eventual^ 

 it forms a thick liquid mass, and with one exception .ill our samples have remained 

 in this condition after settling down Uthough this tendency oi the sepai 

 crystallised eudesmol to revert to the semi-liquid form is so pronounced, yel 

 under some conditions which a1 present are not cleai this change has nol taken 

 place, and we have in oui possession one sample distilled from the oil oi 



Plate LXXXV. 



jrd stage. 



-•nd stage. 



i St stagr 



Illustrating the Unstable Nature of Eudesmol 

 from Eucalyptus Oils, in Three Stages. 



i 11 description see page 376.) 



E. camphora twenty years ago, and thus separated in the crude condition, which 

 has remained in the crystallised form all that time. In other cases eudesmol 

 prepared from the oil oi this species has liquefied after a few months. We also 

 possess one sample of eudesmol separated from the oil of /:'. Macarthuri, which 

 lias remained in the crystallised condition lor two years, and at present shows 

 bni little sie.ns oi alteration, whilst other specimens from the oil of this species, 

 disti led at varying times oi the year, have liquefied alter a few months, although 

 they had been prepared in exactly the same manner. As shown later it is 

 possible to partly change this liquefied eudesmol back to the crystallised form. 



Under natural conditions crystallised eudesmol appears to occur more 

 frequently, and in greater abundance, in the oils oi species belonging to the more 

 recent groups in the evolutionary sequence of the genus, as the " Peppermints," 



