200 



(r) Chemistry of the Leaf Oil. 



The yield of oil from the leaves of this species, although practically constant. 

 is considerably less in amount than is always obtained from similar material of 

 C. glauca. The ester content, however, is nearly three times as great as that 

 occurring in the oil of the latter species, and the acetic acid ester of geraniol is 

 present in large amount also. The laevo-rotatory limonene, too, is more pronounced 

 in the oil of C. culatrdia than in that of C. glaiica, in which species the predominant 

 limonene is found to be always dextro-rotatory. From the results given by the 

 Shuttleton sample, the laevo-rotatorv limonene appears to predominate in C. cal- 

 carata during the summer months. The alteration in rotation is thus mostly with 

 the members of the limonene group, as the ester content and the pinene appear to 

 differ but slightly in amount. The melting point of the tetrabromide formed with 

 the limonene is always high, and this indicates the presence of dipentene also, as 

 well as the active form of limonene. It may be assumed, therefore, that both the 

 dextro- and lie\-o-rotatory limonenes occur together in the leaf oil of this species, as 

 well as in the leaf oils of most other species of this genus. The speciiic graA-ity, boil- 

 ing point, and other characteristics of this terpene, show it to be limonene. From 

 the chemical results obtained with C. calcarata and C. glauca, it is readily 

 seen that they have marked distinctive properties, and could never be confounded 

 one with the other. The free acids of the esters were found to consist almost 

 entirely of acetic acid, and only a small amount of an acid of a higher molecular 

 weight was present ; this acid is most probably butj'ric, as with the esters of 

 C. glauca. The borneol occurring in the oil of C. calcarata is dextro-rotatory, and 

 its acetate also rotates to the right. The lower boiling terpene is dextro-rotatory 

 pinene; and this was proved b\- the formation of its characteristic compounds. 



Sylvestrene could not be detected, nor does it apjiear to occur in the oils 

 of any species of Callitris. 



No. 1. — This material was collected at Wellington, New South Wales, 250 

 miles west of Sydney, on the 9th March, 1903. The terminal branchlets, which 

 were almost entirely free from fruits, were used, and these were distilled for six 

 hours. The weight of the material was 519 lb. and this gave 14 oz. of oil, equal to 

 o-i68 per cent. The crude oil was of a light lemon colour, and had a somewhat 

 distinctive aromatic odour, due to the large amount of geranyl-acetate present. 

 The oil was quite distinct from that of C. glauca, and was also less volatile than 

 the oil of that species, and for a similar reason. The specific gravity of the crude 

 oil at W" C. = 0-8949; rotation, «„ = 4- 11-7°; and the refractive index at ig° C. 

 = 1-4747. When freshly distilled it was somewhat readily soluble in alcohol, but 

 on keeping, it became less soluble. After some considerable time had elapsed the 

 crude oil was still soluble in one volume 80 per cent, alcohol, JMit became turbid 

 with two volumes; it thus differs m solubilitv in alcohol from the oil of C. glauca. 

 There was also no deposition of resin on the sides of the bottle, as was the case 



