(F.v.M., in Journ. Linn. Soc, iii, 87.) Coolabah or Tangoon.

Systematic - A tree attaining a height of 80 feet, and a stem diameter of 4 feet (H. K. Bennett). Bark rough, more or less dark or ashy-grey outside, sometimes persistent, but occasionally smooth (F.v.M.). Leaves lanceolate, falcate, always drying a light slate colour, oblique, measuring sometimes up to 8 or 9 inches in length and 3/4 inch in width, on a petiole of 1 inch or 1 1/2 inch long; venation fairly prominent, intramarginal one not far removed from the edge. Flowers mostly in terminal panicles. Calyx tube small, almost hemispherical; operculum conical, acuminate.

Fruit. - Small, hemispherical, on a slender pedicel; rim thin; valves expanded and much exserted and convex; under 2 lines in diameter. These fruits stand alone as regards their shape.

Habitat. - From Narrabri to the deserts of the north-west of New South Wales; South Australia; Queensland; North Australia,

REMARKS. - Bentham (B. Fl, iii, p. 223) placed this species under E. brachypoda, Turcz., a Western Australian Eucalyptus, but Mueller, in his Eucalyptographia, restores it to specific rank, mentioning that Drummond's specimens, upon which Bentham worked, were without fruits. The species is a good one, and the tree has an extensive range over the interior, where it is one of the largest of the Genus. It is rough barked, the ulterior branches being smooth; the timber is reddish in colour, hard, and durable. It is chiefly characterised by its small hemispherical fruits, with prominently protruding valves. It is known by several vernacular names throughout its geographical distribution, besides the above, such as "Swamp Box," "Goborro," etc.

ESSENTIAL OIL. - Leaves and terminal branchlets for distillation were obtained from Narrabri, N.S.W., in April, 1902. The yield of oil was 0.48 per cent. The crude oil was reddish in colour, and had an odour reminding strongly of cymene. A considerable quantity of phellandrene was present in the oil, and pinene was also determined. Cineol was present only in small amount, hardly exceeding 5 per cent. in the crude oil. Aldehydes were not detected in the higher boiling portions, but those usually found were present in the lower. When the oil of the third fraction was diffused, a distinct cinnamon odour was detected; this has been noticed in several Eucalyptus oils. The higher boiling portion consisted largely of the sesquiterpene. Free alcoholic bodies were also present.

The crude oil had specific gravity at 150 C. = 0.8855; rotation aD - 27.2°; refractive index at 200 = 1.4838, and was insoluble in 10 volumes 80 per cent. alcohol. The saponification number for the esters and free acid was 4.3.

On rectification, 1 per cent. distilled below 1560 C. (corr.). Between 156-1720, 52 per cent. distilled; between 172-2240, 27 per cent. came over, and between 224-2740, 16 per cent. distilled. These fractions gave the following results: -

The third traction was acetylated; the saponification number had then risen to 38.5, showing the presence of alcoholic bodies in this portion. The alcohol was probably the non-crystallised form of eudesmol, particularly as the crystalline body had not been detected at any time.

This sample of oil had been stored in the dark, and in October, 1919, was again analysed. Very little alteration was observed, except that the specific gravity had increased a little, and the rotation diminished about half. The cineol had not increased. 67 per cent. distilled below 1900 C.

The cineol, determined by the resorcmol method, was 5 per cent. when calculated for the crude oil.

That the higher-boiling portion consisted largely of the sesquiterpene is shown by the results obtained on distillation at 10 millimetres pressure. The principal fraction boiled at 130-1350 C.; had specific gravity at 150 = 0.932; rotation aD + 2.5°; refractive index at 200 = 1.5052, and saponification number after acetylation = 28.5.