221 



116. Eucalyptus marginata. 



(Sin., in Trans. I. inn. Soc., vi, ,;<>-', iSc>2.) 

 Jarrah. 



Systematic.- A large tree, averaging 100 feet in height, the bark persistent 

 and fibrous, but being flaky it is not a true "Stringybark." Leaves ovate- 

 lanceolate or lanceolate, under 5 inches long, acuminate, falcate, paler underneath ; 

 venation prominent, the intramarginal vein looped and well removed from the 

 edge or often quite close, lateral veins numerous, fairly transverse. Peduncles 

 slender, axillary, up to 12 lines in length, with umbels of three to twelve flowers. 

 Buds on pedicels 2 to 3 lines long ; calyx tube turbinate, and half as long as the 

 conical, obtuse operculum. 



Fruit. Ovoid-truncate, contracted at the top ; rim 



incurved and later depressed ; valves small, 



not or only slightly exserted ; about 9 lines 

 long and 8 lines in diameter. 



.4s a carpological specimen it stands alone in form 

 amongst Eucalyptus fruits. 



Habitat. Western Australia. 



ESSENTIAL OIL. Material was received for distillation from Western 

 Australia in June, 1904. Two consignments were forwarded, one collected 

 on the Darling Ranges, the other from the sandy flat country around 

 Perth. The first consisted of leaves from older trees, and was a fair average 

 sample, the other was composed principally of abnormal leaves. Although 

 necessarily a great diversity in material was thus shown, as well as a difference 

 in environment, yet the oils were in very close agreement, both in their chemical 

 and physical properties. A larger amount of the lower-boiling terpenes was 

 present in the oil from the abnormal leaves than in that from the older leaves, 

 although the constituents were the same in both samples. This decrease in 

 the amount of the characteristic low-boiling terpene in the older leaves is usual 

 with most Eucalyptus species, and numerous instances of this fact are recorded 

 throughout this work. We have shown also that the characteristic constituents 

 for the oils of any species are common to both young and old leaves, the variation 

 being in the amount. 



The crude oils were red in colour, and had an odour indicating aroma- 

 dendral. The oil from the " Jarrah " is closely associated with those of such 

 species as the tvpe E. tercticornis and E. pimctata var. didyma, and there is strong 

 evidence to support the idea that this class of trees is more closely associated 

 with those Eucalypts known as " Boxes ' than to any other group. Phellan- 

 drene could not be detected, nor was it to be expected in this class of Eucalyptus 

 trees. Pinene was present in small amount, while cymene was a pronounced 

 constituent, The amount of cineol was less than 10 per cent, in the first fraction, 



