GREY GUM AND ITS ESSENTIAL OIL. 279 
sticky nature that are not volatile. The distillate boiling below 
93° C. is entirely volatile, while the crude oil is not so. 
4, The large fraction, consisting of about 60 per cent. of the 
original oil of Z. pwnctata, is, by such rectification, improved to 
such an extent as to consist very largely of eucalyptol. This oil 
does not contain phellandrene, and is practically as good as it is 
possible to obtain eucalyptus oil commercially, and removes the 
necessity, to a large extent, for the use of pure eucalyptol, parti- 
cularly when the expense of the latter has to be taken into 
consideration. 
IV.—ExpLanaTION OF FIGURES. 
E. punctata, DC. 
Fig. 1—Part of a leaf with the lower surface removed, showing 
the oil glands—some with the oil globule and some 
without it. 
», 2—An oil gland under a higher magnifying power than No. 1, 
the cell being empty. 
» 3—A portion of No. 2 still further magnified; the sphere 
represents the oil globule enclosed in the cell. 
» 4—Stomata. 
1, 5—Transverse section of a leaf. a. epidermis, upper surface. 
b. epidermis lower surface. c. lysigenous oil cell 
(empty). d. lysigenous oil cell containing globule of 
oil. ¢. stomata. f palisade layers. g. spongy 
tissue. h. small vascular bundles. 
Acknowledgments.—We beg to tender our sincerest thanks to 
the following gentlemen who have assisted us in various ways in 
the preparation of this paper :—Dr. R. N. Morris, Superintend- 
ent of Technical Education, for every assistance by placing the 
resources of the Technical College at our disposal; Rev. J. Milne 
Curran, F.c.s., for the micro-photographs of timbers ; Mr. O. E 
Finckh, for section cutting of the leaves; Mr. M. Connelly, for 
photographical work ; Mr. 0. Blacket, for timber tests; Mr. F. 
Camroux and Mr. H. T. Gould, Manager Tas. Eue. Oil Co., for 
sample of Z. globulus oil. 
