74 



ESSENTIAL OIL. Material consisting of leaves and terminal branchlets 

 Was received for distillation from the Conservator of Forests of South Australia 

 (Mr. Walter Gill), in December, 1911. 



The yield of oil was 0-02 per cent., only i oz. of oil being obtained from 

 329 Ib. of material. The species is thus a very poor oil-producing Eucalypt. 

 The crude oil was somewhat mobile, of a dark-amber colour, and with an odour 

 indicating an oil of the pinene-cineol group. The amount of cineol was small ; 

 certainly not more than about 15 per cent, of that constituent being present. 

 The saponification number for the esters and free acid was 22-1, which, for an 

 alcohol belonging to the C IO H I7 OH series, in combination with acetic acid, 

 represents 7-7 per cent, of ester. The odour of the separated oil was not distinc- 

 tive, and did not indicate geraniol, so that the identity of the alcohol is at present 

 in doubt. Possibly it may be terpineol. 



The crude oil had specific gravity at 15 C. = 0-9041; rotation D + 6-3; 

 refractive index at 20 = 1-4789, and was scarcely soluble in 10 volumes 80 per 

 cent, alcohol. 



The small amount of oil at our disposal did not permit of more extensive 

 investigation, and distillation results were not obtained. The species has no 

 value as an oil producing tree, the yield of oil being so small. , 



The results obtained with the oil of this species were published by us in 

 the Trans. Roy. Soc., South Australia, 1916. 



31. Eucalyptus megacarpa. 



(F.v.M., Fragm., ii, 70.) 



Blue Gum. 

 (The " Blue Gum " of Donnybrook, or the " Bullich " of the Jarrah Belt, W.A.) 



Systematic. A medium-sized tree, bark smooth when fresh, but becoming 

 rough on exposure. Abnormal leaves elliptical ovate, about 4 inches long and 

 2 inches wide, shortly petiolate. Normal leaves lanceolate, 4 to 6 inches 

 long, falcate, thick, shining; venation not conspicuous, lateral veins oblique 

 and fine, intramarginal vein somewhat removed from the edge. Peduncles 

 axillary or lateral, short, thick, flat, each bearing one to three sessile flowers. 

 Calyx tube broad, turbinate, under 6 lines long, slightly longer than the conical 

 or hemispherical, short pointed operculum. 



Fruit. - Hemispherical, large, ribbed, or almost 

 smooth; rim narrow, slightly convex, con- 

 tinuous with the thick, conical, obtuse, 

 incurved valves ; f to i inch in diameter. 



They have some resemblance to E. globulus in general 

 shape and surface, but not in the disposition of the 

 valves. 



Habitat. Western Australia. 



