10 



The differences in results recorded for the oil oi E. amygdalina in various 

 works on " Essential Oils " can be accounted for in the same way, and this is 

 probably so in all cases where the oil of E. amygdalina is recorded as showing 

 great variability. 



It only requires to be mentioned that the constituents of the oil of 

 E. globulus are practically constant from whatever locality the material is 

 obtained, and the sample of oil from this species that we distilled from material 

 collected at Jenolan, New South Wales, differed in no respect from the product 

 of trees growing in Tasmania, or in Victoria. M. Voiry, in his paper, Compt. 

 Rendus, 1888, p. 1419, also expresses this constancy in the following paragraph : 

 " Cette propriete est commune a tous les echantillons d'essence d' Eucalyptus 

 globulus de differentes provenances que j'ai pu examiner 



Messrs. Faulding & Co., of Adelaide, in 1901, kindly supplied us with the 

 crude oil of E. cneorijolia. The oil of this species is usually laevo-rotatory, the 

 laevo-rotation being caused by the aldehyde aromadendral ; and not by phellan- 

 drene, as that terpene does not occur in this oil. The oil had a rotation in a 

 loo-mm. tube, for the crude oil, of 5-4; that of the rectified oil being 

 -3-0 ; the specific gravity of the crude oil was 0-9287 at 15 C. An analysis 

 made in 1891 by Mr. Robert H. Davies, of Apothecaries Hall, London, of the 

 oil of E. cneorijolia for Messrs. W. Gumming & Co., Adelaide, showed the sample 

 to have a rotation in a-ioo-mm. tube of 3'53, and a specific gravity at 60 F. 

 of 0-923. 



A recent analysis of the oil of this species published in this work, also 

 shows concordant results, so that with this species there is a remarkable 

 agreement also, particularly as this is one of the heavy Eucalyptus oils. 



The oil of E. hemiphloia, in the work on " Volatile Oils," by Gildemeister 

 and Hoffmann, published by Messrs. Schimmel & Co., is stated to contain cineol 

 and a large amount of cuminic aldehyde (now shown to be laevo-rotatory aroma- 

 dendral). Our results showed cineol to be present in good quantity, and aroma- 

 dendral also. It was from the oil of E. hemiphloia that the aromadendral 

 was prepared for the purpose of research. E. hemiphloia is a well-defined species, 

 and but little error should arise in its determination, consequently results 

 agree. 



In this connection it might be well to refer to E. h&mastoma. This species 

 was named by Dr. Smith, in 1/97, from trees growing at Sydney, in which 

 neighbourhood it still occurs, so that there is little doubt as to the particular 

 tree referred to by him. But there is one species (now E. Wilkinsoniana, R.T.B.), 

 which was for a long time thought to be a " Stringybark " form of E. hcemastoma. 

 If someone had investigated the oil stated to have been distilled from this species 

 and supplied under the name E. h&mastoma, different results would certainly 

 have been obtained, the oil of E. Wilkinsoniana consisting very largely of 

 laevo-pinene. 



The " Red-flowering Ironbark " (Eucalyptus sideroxylon] is a species which 

 extends over a large area of country, so that it was possible to obtain material 

 from localities very widely separated. Throughout this area the morphological 

 characters of the species are practically constant, and the nature of the bark 

 and timber shows no variation in general characters a remark which is also 

 applicable to the other species enumerated in this work. Leaves were received 

 from Liverpool, near Sydney, in December, 1900; from Condobolin in March, 

 1901 ; and from Narrabri in July, 1901. These localities are about 350 miles 

 apart, and if connected would form almost an equilateral triangle. The crude 

 oils were in all three cases practically identical, only differing in the amounts of 

 constituents, as might be expected from trees belonging to identical species, 



