(F.v.M.)

Systematic. - A "Mallee" or small tree attaining a diameter of 1 foot, and sometimes up to 30 feet in height, with a smooth bark. The broad expanded base, from which spring a number of small stems, is very characteristic of this species. Branchlets, terete and glaucous. Leaves also glaucous, variable, both in size and shape, perfoliate, sessile cordate, decussate, opposite or alternate; venation faintly marked, lateral veins oblique, spreading, intramarginal vein well removed from the edge. Flowers in short axillary peduncles mostly, generally in threes, sessile or on a short pedicel. Calyx 2 to 3 lines long, 2 lines in diameter, bell-shaped; operculum shortly conical, edge overlapping the calyx.

Fruit. - Hemispherical to elongated or cylindrical; rim thickened, capsule sunk, valves not exserted; up to 5 lines long and under 3 lines in diameter.

E. verrucosa fruits more resemble this than any other.

Habitat. - Tingiringi Mountain and Snowy Mountains, New South Wales, at an elevation of 5,000 feet; north eastern Ranges of Victoria; Tasmania.

REMARKS. - The exudation which gives the common name "Cider Gum" to the Tasmanian Eucalyptus, E. Gunnii, is quite wanting in E. Perriniana. In New South Wales it occurs at an elevation of 5,000 feet, and appears there abruptly without transition forms to connect it with any species occurring on lower elevations. It forms on the highest points a dense Mallee scrub, i.e., small trees up to 4 inches in diameter, springing from a large common root-stock, to the number of six or even more trees. This large root stock is present also when the trees grow singly and to proper tree size, up to 1 foot in diameter. The material of E. Perriniana from Tasmania, again illustrates the constancy of species, for the trees in that Island and on the mainland are identical and show no gradation to E. Gunnii in any way.

Re the Authorship of the species.- - -In our first edition, we gave a description, and the authorship of this species to F.v.M., but later found that Mueller had not published the name or a description, and in our paper on Tasmanian Eucalypts we give a full description, and so put our names after it, not being aware that it had been previously described. Ewart, however (Proc. Roy. Soc, Victoria, vol. 26, p. 3), states that the authorship really belongs to Mr. L. Rodway, who was the first to publish the name and a " not complete description " (Maiden, Crit. Rev . vol. III p. 103). As we now understand that Mr. Rodway is agreeable to let Mueller's name stand with the species, we forego any claim as the authors.

ESSENTIAL OIL. -Material for distillation was collected at Strickland, Tasmania, in July, 1912. The yield of oil was 1 per cent. The crude oil was reddish in colour, but this colour was readily removed, when it had a light amber tint. It contained a considerable amount of cineol. Pinene was present in rather a large quantity for a rich cineol oil, and phellandrene was absent. Volatile aldehydes were pronounced, and these had a very objectionable odour, a character usual with this group of Eucalyptus oils. The odour of the rectified oil was similar to those of the cineol-pinene oils generally. It is a very fair commercial oil for pharmaceutical purposes, although the pinene is a little too pronounced.

The crude oil had specific gravity at 150 C. = 0.9119; rotation aD + 8.90°; refractive index at 200 = 1.4628,. and was soluble in 2 volumes 70 per cent. alcohol. The saponification number for the esters and free acid was 12.3.

On rectification a few drops of acid water and volatile aldehydes came over below 1670 C. (corr.). Between 167.1730, 18 per cent, distilled; between 173-1940, 72 per cent. distilled; the temperature then quickly rose to 2500 with only a few drops, while between 250-2680, 4 per cent. distilled. These fractions gave the following results: -

The cineol was determined by the resorcinol method in the portion distilling below 194° C. and calculated for the crude oil; the result was 68 per cent. By the rapid phosphoric acid method it was 58 per cent, when calculated for the crude oil. The rectified oil of this species is tinged yellow, as is usual with most of the oils of this group. The indication from this is that the predominant phenol is the crystallised one.

The above analysis was published by us in the Proc. Roy. Soc, Tasmania, October, 1912.

In September, 1913, material of this species was received for distillation from Tingiringi Mountain, Southern New South Wales. The yield of oil was 1.1 per cent. The oil was of an amber colour and had a rank odour, cough-producing aldehydes being present in some quantity. In its general characters the oil was similar to that from the species from Tasmania, with the exception that the ester was present in greater amount and the cineol a little less.

The crude oil had specific gravity at 150 C. = 0.9082; rotation aD + 5.7°; refractive index at 200 = 1.4612, and was soluble in 7 volumes 70 per cent. alcohol. The saponification number for the esters and free acid was 52.5.

On rectification 2 per cent. distilled below 167°C. (corr.). Between 167-1730, 11 per cent, distilled; between 173-1930, 63 per cent, distilled, and between 244-268°, 16 per cent, distilled. These fractions gave the following results: -

The saponfication number for the esters in the first traction was 51.4, and in the second 53.4, so that the ester is a low-boiling one.

Another 100 c.c. of the oil was distilled to 1900 C.; the saponification number for the ester in this was 57.2, so that practically the whole ester in the oil was the low-boiling one, determined as the butyl-ester of butyric acid, (See the article dealing with this substance.)

The cineol, determined by the resorcinol method in the portion boiling below 190° C, and calculated for the crude oil, was 50.3 per cent.

When it was found that the ester in the oil of this species was a low-boiling one it was decided to revert to the original oil from the Tasmanian trees; fortunately the fractions had been preserved. The saponification number for the esters in the first fraction was 45.8, so that here again the greater portion of the esters was the low-boiling one, and from the odour and other tests was evidently butyl-butyrate, as in the oil from the New South Wales material.