t 5 6 



83. Eucalyptus longicornis. 



(F.v.M., in Fragm. XI, 14, 1878.) 

 Morrel. 



Systematic. — A tree attaining a height of 120 feet, with a rugose, ash- 

 coloured bark on the trunk, persisting to the branches. Leaves lanceolate, 

 acuminate, about 4 inches long, thick and smooth, venation not conspicuous. 

 Peduncles axillary or lateral, each bearing three to nine pedicellate flowers. Calyx 

 tube semi-ovoid or turbinate, less than half as long as the conical, obtuse 

 or acute operculum. 



Fruit.— Ovoid or turbinate, truncate, sometimes 

 contracted at the orifice ; rim flat or con- 

 cave ; points of the valves formed by the 

 split base of the style, acuminate, often 

 connivent, much exserted. 



These fruits so much resemble those of E. oleosa, 

 except for the coalescing of the valves at the f top, that 

 it teas not thought necessary to depict them. 



Habitat. —Western Australia. 



ESSENTIAL OIL.— This sample of oil was distilled by Mr. P. R. H. St. 



John, in Melbourne, September, 1919. the material being collected from trees 

 cultivated in the Botanic Gardens of that city. The yield of oil was 1-2 per 

 cent. The crude oil was but little coloured, had an odour similar to those of 

 the cineol-pinene oils generally, with a secondary aromatic one. Volatile 

 aldehydes were not pronounced. The constituents present were dextro-rotatory 

 pinene, cineol, esters, alcoholic bodies, and some sesquiterpene. Phellandrene 

 was not detected. 



The crude oil had specific gravity at 15 C. = 0-9203 ; rotation a p + 5-0° ; 

 refractive index at 20 = 1-4670, and was soluble in i£ volumes 70 per cent, 

 alcohol. The saponification number for the esters and free acid was io-8 bv 

 heating. There were no esters saponified in the cold. After acetylation, the 

 sapon ; fixation number was 51-9, of which amount 45-7 was saponified in the cold 

 with two hours' contact. This result represents n per cent, of free alcohols 

 calculated lor the C IO H l8 molecule. 



On rectification, 2 per cent, distilled below 160 C. (corrA Between 

 160-172°, 20 per cent, distilled; between 172-193°, 62 per cent, came over; 

 between 193-2.22 °, 8 per cent, distilled, and between 222^265°, 7 per cent. 

 These fractions gave the following results :— 



First fraction, sp. gr. at 15° C. = 0-8992; rotation" a D -f i3 - 8°; refractive 



index at 20° = 1-4615. 

 Second ,, ,, = 0-9157; rotation a D -\- 5-5°; refractive 



index at 20° = 1-4645. 

 Third ,, ,, =0-9430; rotation a D -- 5-2°; refractive 



index at 20° = 1-4744. 

 Fourth ,, ,, =0-9527; rotation a D — 6-o°; refractive 



index at 20° = 1-4956. 



