245 



chief constituents were dextro-rotatory pinene, laevo-rotatory phellandrene, 

 cineol, geranyl-acetate, free geraniol, together with a small amount of an undeter- 

 mined alcohol, and its ester, and also a solid paraffin-like stearoptene. A 

 substance of such a character had not previously been recorded for Eucalyptus 

 oils ; it is not, however, peculiar to this species, for it has already been found in 

 the oils of some New South Wales Eucalypts. It most probably belongs to 

 the C n H 2n -(-2 group, as it is saturated. This solid aliphatic stearoptene is 

 related to a similar substance found in Rose oil, although melting at a higher 

 temperature, and it is remarkable that the principal alcohol in both Rose oil and 

 in the oil of this Eucalypt is geraniol. The oil of E. Macarthuri, however, does 

 not contain it. Similar paraffins, with varying melting points, have been isolated 

 from the oils of a few other plants, and in some cases from the oils of their leaves. 

 The stearoptene from E. acervula is without doubt from the oil of the leaves, 

 because the trees were not in flower at this time of the year. 



The oil of E. acervula does not agree entirely in general characters with 

 that of E. paludosa of New South Wales, as the former contains a small quantity 

 of phellandrene and not much pinene, while the principal terpene in the oil 

 of E. paludosa is pinene, and phellandrene appears to be absent. The esters, 

 too, were not identical in composition. They both contained, however, about 

 the same amount of cineol, and the paraffin stearoptene was also found in both, 

 but in much smaller quantity in the oil of E. paludosa. The two species may, 

 therefore, be considered as closely related. 



The specific gravity of the crude oil at 15 C. = 0-8956 ; rotation a D 1-1; 

 refractive index at 20 = 1-4747, and it was soluble in i volume 80 per cent, 

 alcohol, but became turbid with 4 volumes, and remained turbid with further 

 addition of alcohol in the cold, forming a flocculent precipitate on standing. On 

 heating the solution it became clear, but the paraffin was deposited again on 

 cooling. 



The saponification number for the esters and free acid was 32-8 by boiling, 

 and 21-4 in the cold with two hours' contact ; this represents 7-5 per cent, of geranyl- 

 acetate in the crude oil, and 4 per cent, of another ester if calculated for an alcohol 

 having a similar molecular weight. The odour of geraniol in the separated oil, 

 after saponification, was very pronounced, and although the amount of oil at 

 our disposal did not permit of its separation and purification, yet there is no 

 doubt as to its identity, particularly as geraniol and geranyl-acetate are such 

 common constituents in certain classes of Eucalyptus oils. 



The amount of free geraniol in the oil was considerable, and another 

 undetermined alcohol was also present. A portion of the crude oil was acetylated 

 by boiling with acetic anhydride and anhydrous sodium-acetate in the usual 

 manner; the separated oil was mobile, and had an odour of geranyl-acetate. 

 The saponification number for this esterised oil by boiling was 105-3, an d in 

 the cold with two hours' contact, 69-5. This latter figure represents 24-3 

 per cent, of ester as geranyl-acetate, and indicates that 13-2 per cent, of free 

 geraniol was present in the oil, as well as 6-6 per cent, of another alcohol, assumed 

 to have the same molecular weight. 



It is worthy of notice that over 50 years ago, when this species was de- 

 scribed by Hooker in his "Flora Tasmania?," he remarked that "The bruised 

 foliage has a much sweeter odour than is usual in the Genus." The discovery of 

 geraniol and its ester in the oil not only confirms this remark, but also indicates 

 the constant character of the chemical constituents. 



The acid in the original ester was separated and found to be almost entirely 

 acetic. 



