AUSTRALIAN MELALEUCAS AND THEIR ESSENTIAL OILS. 367 



tissues of the other two) but occasionally a few parenchyma 

 cells extend around it to the cuticle. The epidermal cells 

 are small and irregularly rectangular in shape. The 

 lysigenous oil glands are few and scattered throughout the 

 leaf tissue. Some sections show the presence of the man- 

 ganese compound in the cells. 



Essential Oil.— The results obtained with the oil of this 

 species again illustrate the fact brought forward in our 

 last Melaleuca paper (Part III of this series), that the 

 chemical characters of ordinary "Cajuput" oil are not 

 representative of the group of essential oils obtainable from 

 the Melaleucas. The constituents of the oil of each species 

 appear to be representative and characteristic for that 

 species wherever found growing naturally. Since our last 

 paper we have obtained material of M. bract eata from 

 Kinbombi in Queensland, hundreds of miles from the pre- 

 vious locality, and the'oil distilled at the Museum from that 

 material was identical in character with that described for 

 this species (Proc. this Society, Dec. 1910). 



The oil of M. genisiifolia was distilled in Victoria in 

 1862 by Mr. Bosisto, but he only obtained 0*07 per cent, of 

 oil from the leaves and branchlets, and no data are given 

 as to the character of the oil. Our results as to yield do 

 not agree with the above, as we obtained over half per 

 cent, of oil from our material, which also consisted of the 

 leaves and terminal branchlets like that which would be 

 used commercially. 



The oil of M. genistifolia consists very largely of dextro- 

 rotatory pinene — which has a very high rotation — and is 

 almost devoid of cineol, less than 2 per cent, of that con- 

 stituent being present in the crude oil. As the oil contains 

 between 80 and 90 per cent, of pinene, it might have some 

 economic value as a "turpentine" producing plant, pro- 

 viding the yield of oil was greater than it is. 



