EUCALYPTUS TREES. £3 
The illus- 
tration at Fig. x 
VI. exhibits 
the form and- 
arrangements 
of the cells 
and also of the 
trans- and 
respiration- 
pores (stoma- 
ta) in the cu- 
ticle (epider- 
mis) of the |\ 
leaves of Eu- 
calyptus glo- 
bulus. About 
22,000 stoma- 
ta occur on a 
square inch 
of either side, 
whereas in VILN Reva ®) 
most other Fic. VI.—Cellular cuticle of a leaf of Eucalyptus globulus, 
plants the showing also the breathing pores, magnified 300 times. 
breathing 
pores on the lower side of a leaf vastly outnumber those of the 
upper side, or in numerous instances none even may occur on 
the upper page. Vast as the numbers of these stomata are also 
in Eucalypts, they are still far less numerous than those of the 
lower side of a Lilac- or Turnip-leaf. The particular cellular 
structure of the epidermis and the shape and manner of dispersion 
of the stomata afford marks of characteristics for many genera 
and even species of plants. 
The Blue Gum-tree has been preferentially reared in fever- 
regions of various countries, in warm temperate zones, to subdue 
malarian influences by the exhalations of its antiseptic oil; and 
this volatile oil is also administered, as a disinfectant medicine, to 
arrest processes of putridity in various diseases. Besides it has 
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