i8 7 



98. Eucalyptus dumosa. 



(A. Cunn., Schau. in Walp. Rep., ii, 925.) 

 Bull Mallee. 



Systematic. Found only in the dry interior of the Continent, and rarely 

 attains tree form. The bark is white and smooth. Leaves lanceolate, 

 under 4 inches long, shortly acuminate, coriaceous, shining, of a dull yellow 

 colour ; venation fairly prominent, lateral veins distinct, intramarginal one removed 

 from the edge. Oil glands quite obscured. Peduncles axillary, short, bearing 

 a few flowers on short pedicels. Calyx tube cylindrical, occasionally angular, 

 almost 3 lines long ; operculum short, conical. 



Fruit. Shortly pedicellate or sessile, obovoid or 

 oblong, slightly ribbed ; rim narrow, sunken ; 

 valves slightly exserted ; about 3 lines long. 



The fruits might he mistaken for a smalt variety of 

 E. costata. 



Habitat. Southern interior of New South Wales; South Austra- 

 lia ; Victoria The Kangaroo Island species has a 

 coarser fruit. 



REMARKS. This species was considered by Baron von Mueller us a variety of E. incrassata, Labill., 

 but Bentham records them as specifically distinct in the Flora Anstraliensis, and judging from the material in the 

 National Herbarium, Melbourne, we think Bentham is correct in his classification. Labillardiere's species has a 

 larger fruit than A. Cunningham's E. dumosa. The former species occurs so far west from this State that it was 

 found impracticable to procure either leaves for distillation or specimens of timber. The fruit of H. diimosa often 

 has the facies of E. oleosa, when the valves are exserted. 



ESSENTIAL OIL. Leaves and terminal branchlets for distillation were 

 obtained from Coolabah, N.S.W., in October, 1900. The yield of oil was i per 

 cent. The crude oil was amber coloured, and had an odour resembling those 

 belonging to the cineol-pinene class, and a secondary one indicating the aldehyde 

 aromadendral. The oil was not very rich in cineol; it contained pinene, but 

 phellandrene was absent. Aromadendral was probably present, although the 

 dextro-rotation of the higher boiling portion suggests the presence of the liquid 

 form of eudesmol. 



The crude oil had specific gravity at 15 C. = 0-9151 ; rotation D + 5-8; 

 refractive index at 20 1-4703, and was soluble in if volumes 70 per cent! 

 alcohol. The saponification number for the esters and free acid was 2-93. 



On rectification the usual amount of volatile aldehydes came over below 

 163 C. (corr.). Between 163-183, 86 per cent, distilled; (24 per cent, below 

 171); between 183-237, 8 per cent, distilled. These fractions gave the following 

 results : 



First fraction, sp. gr. at 15 C. = 0-9127 ; rotation a D + 7-8. 

 Second ,, ,, ,, = 0-9405; ,, + 9-1. 



The cineol, determined by the phosphoric acid in the large fraction, was 

 50 per cent., indicating about 44 per cent, in the crude oil (O.M.). 



