24. Eucalyptus umbra. 



R I B Proi . I inn, Soi . N.S.W., igoi, p. 687, 1 XI [V 

 Stringybark, White Mahogany. 



Systematic. — A tall tree, attaining sometimes .1 height oi i",, feet, with 

 a dark-coloured stringy bark. Abnormal leaves opposite, sessile, cordate, ovate, 

 acuminate, thin, pale-coloured on the underside; venation more pronounced 

 on the underside, upper surface shining ; over 3 indies broad, and under 6 inches 

 long. Normal leaves lanceolate, falcate, large, up to 9 inches long and i\ inch 

 broad, pale-coloured on both sides, coriaceous ; venation distinct, lateral veins 

 spreading, oblique; intramarginal vein removed from the edge. Flowers on 

 short axillary peduncles, six to nine in the umbel. Calyx 1 line long, on a 

 pedicel about 2 lines long; operculum hemispherical, shortly acuminate. 

 t 



Fruit. In the early stage, pilular and under 3 lines 

 in diameter, the rim and valves sunk, like 

 E. acmenioides and E. camea, but in the 

 mature stage hemispherical, or inclined 

 to be pear-shaped, with a diameter of 5 

 lines, and a very thick red, truncate or 

 slightly domed rim, when the fruits much 

 nsernble those of E. hczmastoma and E. 

 coriacea. 



Habitat, ["hi 1 oa 1 di trid north from Sydney, N SAY. 



REMARKS. IK'' earl) fruits oi thi-^ species have .1 remarkable resemblan 



mi h so 1 li.'t in liei 1 iai turn matei ial 1 lie two vej probab icter ha ■ 



confounded in tin past. The two species differ, however, consideral rture .clour and venation 



of the leaves, .1^ well as in the mature fruits, which have .1 broad run. E. acmenioides, Schau., has thin 1 



with a pale undei surfi vh < 1 undoubtedly resemble those of A .1- now understood), Inn 



those ■' are oi a uniform colour on both "l' Longei nil broader, and with a very marked venation 



much like that of E. patentinervis K. 1 B ["he abnormal leavi an also quiti di tincl fi in I nioides. 



■ ired. 



ESSENTIAL OIL. Leaves and terminal branchlets for distillation wen- 

 obtained at Gosford, N.S.W., in August, 1899. The yield oi oil was o-6 pei 

 ■ int. The trude oil was oi a light amber colour, and had an odour resembling 

 those oi the pinehe-cineol class generally. Pinene was presenl in quantity, but 

 phellandrene was absent. Cineol was also a pronounced constituent. The higher 

 boiling portions consisted largely oi the sesquiterpene, and eudesmol was no1 

 detected. Although resembling in general characters the oil oi E. camea, ye1 

 n contained much less estei and considerably more cineol, and it thus appi 

 that these two tiers arc nut identii al spa ii 



The crude oil had specifii gravity at 15 C. 0-8970; rotation a D -f- 18-7° ; 

 refractive index at _'o° = 1-4639, and was soluble in 5 volumes 80 per cent. 

 il, ohol 1 h< 5aponifii ation number foi the esters and frei a< id was ;-i. 



