jo 2 



163. Eucalyptus tceniola. 



(R.T.B. & H.G.S., Roy. Soc. Tas., p. [98, 1912.) 



Systematic. A tree of about 40 to 50 feet high and 2 feet in diameter, 

 with a " peppermint ' : bark. Abnormal leaves opposite or alternate linear, 

 lanceolate straight, 4 to 6 inches long and \ inch wide. Normal leaves narrow, 

 linear to linear-lanceolate, thin, up to 12 inches long; venation not pronounced, 

 intramarginal vein removed from the edge lateral veins very oblique. Peduncles 

 axillary, but sometimes apparently paniculate, angular, bearing few flowers. 

 Caylx tube pyriform ; operculum small, compressed, slightly pointed. 



Fruit.— Pear-shaped, tapering to a short pedicel ; 

 rim countersunk ; valves not exserted ; up 

 to 6 lines long and 3 lines wide. 



Morphologically they could easily be mistaken for 

 E. virgata, Sieb., of this work. 



Habitat. — St. Mary's Pass, Tasmania. 



REMARKS. — A species endemic to Tasmania and of restricted distribution in that Island. 



ESSENTIAL OIL.— Material of this tree was collected for distillation at 

 St. Mary's, Tasmania, in June, 1912. The yield of oil was o-66 per cent. The 

 crude oil was little-coloured, had a terpene odour, and contained much phellan- 

 drene ; scarcely any pinene occurs, and only a very small amount of cineol. Eudes- 

 mol was detected. The oil belongs to the " Peppermint " group of Eucalypts, 

 as it contained a small amount of piperitone. A considerable quantity of high- 

 boiling constituents was also present, which consisted largely of the sesquiterpene. 

 The yield of oil was too small for it to have commercial value. 



The specific gravity of the crude oil at 15 C. = 0-8864 '< rotation a D — 27-6° ; 

 refractive index at 20 = 1-4844, and was soluble in 5 volumes 80 per cent, alcohol. 

 The saponification number for the esters and free acid was only 3-2. 



On rectification, a few drops of acid water, and a little volatile aldehydes 



of a not unpleasant odour, came over below 173° C. (corr.). Between 173-198°, 



68 per cent, distilled ; between 198-265°, only 1 c.c. came over, and between 



265-282°, 26 per cent, distilled. These fractions gave the following results : — 



First fraction, sp. gr. at 15° C. = 0-8592; rotation a D - - 45-1°; refractive 



index at 20° = 1-4794. 

 Second ,, ,', ,, = 0-9408; dextro-rotatory 8 to io°, but 



light did not pass well ; refractive index 

 at 20° = 1-5015. 



The dextrorotation of the higher-boiling fraction is due to the presence 

 of eudesmol. 



The cineol was determined by the resorcinol method in the portion distilling 

 below 198° ; when calculated for the crude oil the result was 7 per cent. 



These results indicate that this Eucalypt is somewhat closely associated 

 with the Tasmanian E. virgata. The oil from the latter, however, contained more 

 cineol and more eudesmol, while that of E. tceniola had more phellandrene, as 

 indicated by the rotation figures. 



The analysis of the oil of this species was published by us in the Proc. Roy, 

 Soc, Tasmania, October, 1912, 



