AUSTRALIAN MELALEUCAS AND THEIR ESSENTIAL OILS. 63 
developed, as also are the numerous and spacious air 
cavities into which they lead, and these form a marked 
feature of the section. 
Below the epidermal cells of the upper surface are found 
characteristically arranged cells, t.e., the palisade paren- 
chyma, which is composed of a double row of closely 
opposed columnar celis, whilst below the lower surface one 
row of palisade cells only occurs. The palisade parenchyma 
encloses a loosely disposed area of spongy parenchyma. 
The position of the midrib and a lateral vein hear each 
edge of the leaf is well brought out in the plate, and each 
is seen to be constituted by a fibro-vascular bundle con- 
sisting of en. endodermic cells, 8. scelerenchymatous 
conjunctive tissue or woody fibre, T. bast, C. cambium, 
wax Vem, 
G. Briosi in his research on the leaves of Eucalyptus 
globulus, Labill., published by Istituto botanico della R. 
Universiti di Pavia, (1891) names the cells which I make 
to be similar to en. as collenchymatous, but as no 
thickening of the walls at the angles could be found, I have 
preferred to classify those in this instance as endodermic. 
Essential Oil—The yield of oil of this species is con- 
siderable, no less than 82% ounces of oil being obtained 
from 227 pounds of leaves with terminal branchlets, equal 
to 2°28." The material was collected in the month of 
April in the neighbourhood of Sydney. The crude oil was 
but slightly coloured, it being yellowish in tint. The 
rectified oil was colourless. In appearance, odour and 
taste it differed but slightly from those Hucalyptus oils 
which are rich in eucalyptol, and which do not contain 
either the aldehyde aromadendral or the terpene phellan- 
1 J. F. Bailey (Queensland Flora) gives the yield of oil as 13 ounces 
from 112 pounds, which is only about % per cent. The pronounced oil 
glands in the leaf of this species, however, indicate a large yield of oil. 
