-VI 



The mixed crude oils ol .ill the samples had specifii gravit} al 15 C. = 

 0*929; refractive index a1 20 ['4745, and was soluble in 2 volumes 70 pei 

 cent, alcohol. The saponifii ation number for the est< 1 - and free a< id was 8-4. 



On rectification, 2 pei cenl distilled below i-_> c. i.corr.). Between 

 [72 C76 . 23 per cent, ctystilled ; between 1 ~' > [86 . 32 pei cent, came over; 

 /een [86 268 . u pei cent, distilled, and between 268-289 , 27 per cent. 

 distilled. These fractions gave the following results: — 



First fraction, sp. gr. at 15 C. = 0*9025; rotation a [*o . 

 S( 1 ond ., ,, .. = 0-907') ; ,, ina< ii\ e. 



Third .. ,. .. = 0*9132 ; „ a D +1*4°. 



Fourth ,. ,. ., = 0-95(1 1 ; .. not taken. 



The cineol, determined by the phosphoric acid method in the oil distilling 

 In 'low [86 . wa - 52 per cent., indicating about 30 per cent, in the crude oil (O.M.). 



Myrticolorin. The leaves of E. macrorhyncha contain a large amount 

 of a yellow dye material, discovered by one of us in 1897. (Proc. Roy. Soc, N.S.W.) 

 It was there named Myrticolorin. Its chemistry was afterwards described in a 

 paper (Journ. Chem. Soc, 1898, p. 697). It is a glucoside of quercetin, having the 

 formula C 27 H 3O l6 and on hydrolysis breaks down into quercetin, glucose, and 

 rhamnose bj the Eollowing reaction : ( \,H 3O 0, 6 + 3 H.O = C, 5 H lo 7 + C 6 H,.0 6 + 



1 M A- 



Osyritrin, I iola-quercetin and Rutin, are analogous substances. Myrti- 

 colorin gives colours, when mordanted, resembling those obtained similarly with 

 the better qualities of flavin, and decidedly purer than those given by quercitron 

 bark itself, or with fustic. The colours are quite fast to light and to milling. 

 The extraction of myrticolorin from tlu- leaves of this Eucalyptus is exceedingly 

 simple, but it is important that the leaves be ground to a very fine powder. When 

 the powdered leaves are boiled and filtered boiling hot, the myrticolorin passes 

 with the filtrate, but crystallises out again on cooling, as it is very slightly soluble 

 in cold water. The tannins and other bodies extracted at the same time remain in 

 solution, and can be removed by filtration ; the myrticolorin can then be washed 

 with cold water, pressed, dried, and powdered. A determination, on a semi- 

 commercial scale, gave at the rate ot 8| lbs. of dried myrticolorin from 100 lbs. 

 of powdered leaves, collected as would be done for commercial oil distillation. 

 Eucalyptus macrorhyncha is a common tree in New South Wales and Victoria, so 

 that there is an abundance of material available. 



The presence of this dye material in the leaves of E. macrorhyncha at once 

 distinguishes Li from E. Icevopinea, and is another illustration of the value of 

 chemical evidence in determining differences between Eucalyptus species closelj 

 allied morphologically. [races oi this dye have been detected in the leaves of 

 other species, but, far, the amouni has not been determined. It may be found 

 eventually, however, thai E. mucrorhynclut does not give the maximum yield of 

 this dye material, particularly as the leaves ol some species become quite yellow 

 w hen dry, 



