(Sieb., in DC. Prod., iii, 217.)

Systematic. - An average forest tree, stated by Rodway to attain a height of over 100 feet; branchlets glaucous; bark thick, laminated, running down in ridges, friable, inner portion hard, close, compact, in cross-section, the duramen difficult to determine from the normal wood. Abnormal leaves mostly alternate, petiolate, sometimes glaucous, thin, oval-lanceolate to lanceolate, acuminate, 4 to 5 inches long, up to 1 1/2 inch broad; venation distinctly marked, lateral veins not very oblique, intramarginal vein removed from the edge. Normal leaves comparatively small, rarely 5 inches long, mostly from 2 to 4 inches long, up to \ inch broad, lanceolate, shining, sub-coriaceous; venation inconspicuous, lateral veins well oblique, a few running almost longitudinally parallel from the petiole; intramarginal vein removed from the edge. Flowers on axillary peduncles or in short panicles; operculum hemispherical, shortly acuminate.

Fruit. - Pyriform, contracted at the top; rim countersunk; valves inserted; up to 6 lines long, 3 lines in diameter.

The differences between E. virgata, Sieb., and E. Sieberiana are found principally in the smaller leaves, countersunk rim of the smaller fruits, timber, and chemical constituents of the oil of the former. They are rather difficult to separate in herbarium material alone.

Habitat. - Springwood, Lawson, Mount Victoria, Blue Mountains, New South Wales; Tasmania.

REMARKS. - From Sieber's specific name there can be little doubt but that he intended his description to apply to a small twiggy Eucalyptus, with exactly the same morphological features (as later researches have shown) as the present "Mountain Ash," B. Sieberiana, F.v.M., and these characteristics of the two species are proved by Bentham's note, B.F1. iii, p. 202, for under E. virgata he states: "I have described this species chiefly from Oldfield's, Woolls', and F. Mueller's specimens; Sieber's appear to be the same, but they are only in the young bud, and therefore uncertain." There is, on the Blue Mountains, a dwarf Eucalyptus, or Mallee," the herbarium material of which cannot be separated from that of the tall tree, E. Sieberiana, but the chemical constituents of each are quite different. It is very probable that Oldlield's, Woolls', and Mueller's specimens belong to the tall tree, known as "Mountain Ash," and since named by Mueller as E. Sieberiana, whilst Sieber's specimens no doubt belong to the dwarf tree or "Mallee," and, as Bentham found, quite impossible of separation in dried material. If this is correct, then Sieber's tree only differs in field and chemical characters, and on these we accept Sieber's name for the mountain shrub which has identical morphological characters with E. Sieberiana, F.v.M.

Our action in regard to this species will, no doubt, be thought to be arbitrary, but we, on our part, think that Oldfield, Woolls, Mueller and others when dealing with type herbarium specimens were in error in supposing that Sieber's specimens and specific name belonged to the "Mountain Ash," E. Sieberiana. Sieber must have collected from a "Mallee" when he bestowed the name E. virgata on his species, and as his specimens almost exactly match those of this larger tree, it would, therefore, be quite easy for Bentham and Mueller also working on these dried materials, to confound these Eucalypts. We were in error ourselves until convinced by the chemical investigation of E. virgata. The results proved conclusively that his views based upon field observations. were quite correct, and we think that the identity of E. virgata of Sieber is now clearly shown. Material of E. Luehmanniana, F.v.M., could never have been confounded with this species, as they are so dissimilar.

In our work on Tasmanian Eucalypts, Roy. Soc. Tas., 1912, we record this species from that Island. where it grows to an average tree size.

The history of this species at the hands of systematista is interesting: - It was described as a species by Sieber, DC., Prod, iii, 217. Bentham in his "Flora Australiensis," vol. iii, 202, gives it specific rank. Mueller, in "Encalyptographia," Dec. 2, [880, places it under E. Sieberiana, and later, Dec. 10, l884, synonymises it under

E. striata; later in his second Census, 1889, he restores the name. Deane and Maiden, in Proc. Linn. Soc, N.B.W., 1897, p. 717, discuss its affinities at great length, and state that it oscillates between E. Luchmanniana and

E. obtitsiflora, and finally that "all that remains is to give the name of E. virgata decent interment....."

Maiden, in his "Critical Revision of the Genus Eucalyptus," Vol. I, p 273, 1907, states that E. virgata and E. stricta are conspecific. Later in the same work, Vol. 4, p. 284, 1919, Maiden raises the tree to specific rank and places it above E. Luehmanniana, F.V.M., Stating, however, that it (E. virgata) is confined to New South Wales.

ESSENTIAL OIL. - Material for distillation was obtained from Spring-wood, N.S.W., in September, 1899. The yield of oil was 0.29 per cent. When distilled the oil was found to consist very largely of crystallised eudesmol, that substance being present in such quantity that the oil solidified in the receiver. A fresh consignment of leaves was then received, and this on distillation gave similar results. The material thus obtained was undoubtedly the most remarkable Eucalyptus oil we had seen up to that time. Only traces of cineol were detected, while the low-boiling terpenes consisted principally of phellandrene. The oil of this species has little resemblance to that obtained from E. Sieberiana, as eudesmol does not occur in the oil of the latter species. The peppermint constituent, piperitone, is present in small amount in the oil of E. virgata. Fresh material of E. Sieberiana was obtained on purpose to test the constancy, but the oil corresponded with that obtainable at all times from the leaves of E. Sieberiana, and had little resemblance to that derived from this species, owing to the absence of eudesmol. The oil distilled from the first consignment of leaves was analysed with the following results: -

The crude oil had specific gravity at 150 C. = 0.9154; refractive index at 200 = 1.4958, and was soluble in 1 volume 80 per cent, alcohol. The saponification number for the esters and free acid was 5.7.

On rectification, 1 per cent, distilled below 173° C. (corr.). Between 173-1880, 54 per cent, distilled; between 188-2720, 10 per cent, came over, and between 272-2850, 31 per cent, distilled. These fractions gave the following results: -

Several years later, in June, 1912, material for distillation was obtained from St. Mary's, Tasmania. The yield of oil was 0.79 per cent., which is greater than that from the N.S.W. trees. The oil consisted largely of phellandrene and eudesmol, the terpene in the greater proportion, and the eudesmol in correspondingly less amount than was present in the Australian oil, otherwise the agreement was very close; this can be seen from the following results. The crude oil was but little coloured, and had a secondary odour of peppermint, due to the presence of a small quantity of piperitone. Cineol was readily detected in small amount.

The principal constituent in this oil was phellandrene, and pinene probably absent. Eudesmol was present in quantity, the high-boiling fraction becoming solid after a few hours. Only a very small amount of ester was present in the crude oil. Although the phellandrene shows the lævo-rotatory modification in excess, yet, judging from the comparatively small rotation, and the almost entire absence of pinene, it seems possible that the phellandrene of opposite rotation was also present. So far dextro-rotatory phellandrene has not been isolated from any Eucalyptus oil.

The crude oil had specific gravity at 15° C. = 0.8883; rotation aD - 20.9°; refractive index at 20° = 1.4810, and was soluble in 3 volumes 80 per cent, alcohol. This comparatively ready solubility is largely due to the presence of eudesmol. The saponification number for the esters and free acid was 3.3.

On rectification, the usual amount of acid water and volatile aldehydes came over below 1730 C. (corr.); the aldehydes however, were much less pungent and objectionable than are those from the oils of the pinene-cineol groups. Between 173-198°, 78 per cent, distilled; the temperature then rose quickly to 265°, only 1 c.c. distilling; between 265-282°, 17 per cent. distilled. These fractions gave the following results: -

The cineol was determined in the first fraction by the resorcinol method; when calculated for the crude oil the result was 21 per cent. Other substances than cineol were evidently absorbed, as only about 10 to 12 per cent. was indicated by other methods. The large amount of eudesmol caused the high-boiling fraction to soon become solid, and this peculiarity is quite a distinguishing feature between the oil of this species and that of E. Sieberiana.