The acetic Acid ester. The amount ol estei oci urring in the oil of thi 

 i- somewhal large, and .1- the redistillation had demonstrated the pn 

 acetic acid, which had been derived from the decomposition oi an 1 

 was decided to proceed further, particularly as the amounl of the free a< id pn 

 in the crude oil was quite small. A quantity of the < rude oil was boili ome 



time with aqueous potash under a condenser, the aqueous portion separated, 

 evaporated down and filtered. Ii was thru acidified with sulphurii 

 the volatile acids distilled ovei until all had been obtaim Qualitati 



showed that acetic acid was present in quantity, but the odour of valerii a. id 

 had aUo been <> so that it is most probable thai bo sent, 



iso the article on the Valerii Acid Ester in Eucalyptu 

 The distillate was exactly neutralised with barium hydi lution, and 



the mixed barium salt purified and prepared 111 the usual - Mi- amount 



of barium was then determined as barium sulphati 0-4858 gram, ol the 

 barium salt mi ignition gave 89-3 per cenl ol BaS0 4 , so that the amount oi bat 

 1 ■ tate in the mixed salt was 90-85 per cent., and the barium valeriate 9-15 pi 1 

 rent., assuming that valeric acid was the onh othei acid present beside-, ac 

 This result suggests that valeric acid may be presenl as an ester in many (rude 



alyptus nib, and to be connected with the valeraldehyde which occui 

 frequently in certain groups. Aceta a. a! is the free acid occurring in Eucalyptus 

 oils, which is demonstrated in the article dealing with this subjed audit is also 

 present in the oil of E. Macarthuri, E. acervula, and other numerous specie- as 

 an ester in combination with geraniol. The alcohol oi the ester occurring in 

 the oil of E. cornea has now been determined, and that it is not geraniol is 

 shown by the ester not saponifying in the cold when treated with alcoholic potash; 

 it was proved to be dextro-rotatory terpineol. 1 1 1 > ■ portion boiling above 

 190 C. was saponified and the separated oil distilled under reduced pressure. 

 A portion was eventually obtained boiling at 99-10.; C. at in millimetres. This 

 had specific gravity 0-93; rotation a D + 60' ; refractive index at 20° = 1*484, 

 and gave a fair yield of phenylurethane melting at no ('. This is further 

 evidence that terpineol was formed early in the genus, similarly with geraniol, 

 and probably continues throughout the oils oi the entire group. 



17. Eucalyptus dextropinea. 



I B . Pro I inn 5oi . N.S.W., 1898, p. 117. t. XI. 

 A Stringybark. 



Systematic- A tree attaining a height oi from 60 i<> coo feel or higher, 

 and a diameter up to g feet Bark dark oi black on the outside, fibrous, and 

 longer in the fibre than that oi E.lavopinea. Branches smooth for a considerable 

 ince down, but this feature s almosl identical with those oi 



E. IcBvopinea oi this work, and resembling also those oi /.. obliqua, L'Hei 

 Abnormal leaves broad, rounded at th >\ acuminate, opposite 01 



no, 11 1- -o, on a shorl petiole, the venation well defined, the intramarginal vein 

 being mui h removed from the edgi Normal leaves lam eolate, falcate, acumin 

 often very oblique, shining on both sides, rather thick, the intramarginal vein 



