47 



14. Eucalyptus acaciceformis. 



(H.D. & J.H.M., Proc. Linn. Soc., N.S.W., 1899, p. 454.) 

 Peppermint. 



Systematic. A large umbrageous tree attaining several feet in diameter, 

 with a " Peppermint " bark. Abnormal leaves alternate, pale-coloured, lanceolate, 

 usually obtuse, margin crenulate, average size about ij inch by f inch. Normal 

 leaves lanceolate, average size 2f inches by ^ inch ; intramarginal vein removed 

 from the edge ; lateral veins parallel, at an angle of about 45 from mid-rib. 

 Peduncles short (i line), angular ; bearing six or seven flowers in the head. 

 Calyx tube short ; operculum about the same length as the calyx, shortly pointed. 



Fruit. Almost sessile, hemispherical; rim narrow, 

 truncate or slightly domed ; valves scarcely 

 exserted ; 2 lines broad and i \ lines long. 



The fruits bear a great resemblance to those of 

 E. Macarthuri, so that the two species cannot be 

 separated on the fruits alone. 



Habitat. New England district, New South Wales. 



REMARKS. The authors, when describing this species, speak of the bark as " Peppermint, stringy, rough 

 and furrowed." If this is correct, then on a cortical classification it would be very difficult to place it in any of the 

 groups of this Genus. However, to us it seems to approach more nearly the bark of the " Peppermint " group in 

 texture. It is one of the numerous so-called " Peppermints " of the New England Tableland. 



ESSENTIAL OIL. Leaves and terminal branchlets for distillation were 

 obtained from Tenterfield in January, 1910. The material was collected as 

 for commercial distillation, so that the yield is an average one. The crude oil 

 was red in colour, very mobile, and had a rank, turpentine-like odour. It 

 consisted principally of dextro-rotatory pinene, and the sesquiterpene. Phel- 

 landrene could not be detected, and cineol was only present in a very small 

 amount. The ester was somewhat large for an oil of this class, and apparently 

 consisted principally of geranyl-acetate. In its general characters the oil of 

 this species has resemblance to that of E. nova-anglica, although the larger amount 

 of dextro-rotatory pinene (with a very high rotation), the less yield of oil, higher 

 ester content, lower specific gravity, and the small quantity of the sesquiterpene, 

 all show it to differ from the oil of that species. The following results were 

 obtained with the crude oil : 



Yield of oil per cent. = 0-20. 



Specific gravity at 15 C. ... ... ... ... : 0-8864. 



Rotation a D + 35'7- 



Refractive index at 20 C. ... ... ... 1-4713. 



Insoluble in 10 vols. 80 per cent, alcohol. 



The saponification number for the esters and free acid was 17-4, while in 

 the cold with two hours' contact it was 16-2. 



This result shows the ester to be principally geranyl-acetate, so that, from 

 the cold saponification, the oil contained 5-7 per cent, of that ester. 



