175 



(c) Chemistry of the Leaf Oil. 



This material was forwarded to us from Port Darwin by Mr. Nicholas 

 Holtze, the Curator of the Botanic Gardens at that place. It was received on 

 the 2nd November, 1904. The leaves and branchlets had been packed with 

 very few twigs, and fruits were absent. 



The crude oil was amber coloured, very mobile, and had an odour some- 

 what resembling the leaf oil of the Callitris species generally, but with a distinct 

 lemon-like odour. The distillation was continued for six hours, and i6g lb. of 

 material gave 3 oz. of oil, equal to o-ii per cent. 



The crude oil was insoluble in ten volumes of go per cent, alcohol. It 

 was practically a terpene oil, consisting largely of laevo-rotatory limonene, dipen- 

 tene, and pinene. The ester content was very small in amount, but it consisted of 

 both borneol and geraniol, probably in combination with acetic acid. The specific 

 gravity of the crude oil at IF C. = 0-8481 ; rotation Ad = — 21-6° ; refractive index 

 at 22° C. = 1-4768. The saponification number was 10-9, equal to 3-81 per cent, 

 esters. Only 25 c.c. of oil could be spared for redistillation, and this com- 

 menced to distil at 156° C. Between 156° and 165,° 36 percent, distilled; between 

 165° and 175° 40 per cent. ; above 175° (left in still), 24 per cent. 



The specific gravity of the first fraction at 20° C. = 0-8457; of the second, 

 0-8435; of the residue, 0-8782. The rotation of the first fraction Ad = — 7-5°; 

 of the second — 25-4°. The rotation of the residue could not be taken, but it 

 must have been highly laevo-rotatory. The refractive index at 20° C. of the first 

 fraction was 1-4749; o^ the second, 1-4752; of the residue, 1-4889. The residue 

 was saponified and the oil separated, when both borneol and geraniol were detected. 

 The volatile acids gave marked reactions for acetic acid, so that the esters were 

 probably those of acetic acid. 



From the above results it is seen that this species has no marked agreement 

 with any other species of Callitris, so far as characteristic properties influence 

 the determination. It is more nearly in agreement with C. arenosa than with 

 any other, but differs from that species by the predominant limonene being 

 laevo-rotatory, while that of C. arenosa is dextro-rotatory. It did not deposit a 

 resin on the bottle on keeping, thus difiering from the leaf oils of C. glauca and 

 like species. 



We had previously received on 29th December, 1903, a small quantity of 

 material of this species from Port Darwin, but it only weighed 36 lb., and was 

 altogether inadequate for our purpose. It was thought desirable, however, to 

 distil it, and the following results were obtained. It will be seen that for such a 

 small amount of oil there is a marked resemblance to that of the other sample. 

 Only about 3 grams of oil could be collected, the specific gravity of which at 



