AND THEIR ESSENTIAL OILS. 43 



per cent, distilled; and between 172-194 C. 63 per cent, 

 came over. These fractions gave the following: 



Sp. Gr. at n Ata , Hef. Index 



15 C. Dotation a D . a tl8C. 



First traction 0-81)67 ... + 16'7 ... 1-4639 



Second fraction .... 0-9086 ... + 9'4 ... 1-4640 



The eucalyptol was determined by the resorcinol 

 method in the portion distilling below 194, and when 

 calculated for the crude oil 59 per cent, of that constituent 

 was shown to be present. 



The saponification number for the esters and free acid 

 \vas 5'9. The oil of this species is thus one of the oils of 

 the eucalyptol-pinene group, which oils are found so fre- 

 quently occurring in the Eucalypts of a certain class. 



The oil of this species and that of E '. Muelleri are very 

 closely related, in fact, almost identical in composition, 

 as can be seen by referring to the results for that species 

 recorded in this paper. 



EUCALYPTUS VIMINALIS, Labill. 



(" Manna Gum.") 



BOTANY. 



Historical. This species was originally named by Labil- 

 lardier from a Tasmanian tree, and has retained its specific 

 status ever since. 



Remarks. This tree has also a very wide distribution 

 on the mainland, where the most common name is " Manna 

 Gum." 



The material here examined corresponds with that from 

 trees growing on the mainland from which our original 

 determinations were made, and published in our work 

 " Eucalypts and Their Essential Oils " (p. 137). 



The variety macrocarpa in Rodway's " Flora of Tas- 

 mania " (p. 57) we have determined as distinct, and 

 specifically described under the name of E. unialata. 



At Alma Tier, Interlaken, are to be found trees growing 

 amongst E. Gun-mi, but different from that species, and 

 known locally as " White Gum" evidently considered 

 by settlers to have affinity with the " Manna Gum," E ' . 

 viminalis, but yet distinct from the " Cider Gum." 



The " sucker " leaves are larger than those of E. 

 viminalis, and resemble those of E. Gunnii; then, again, 

 the normal ones are larger and broader than usually 

 obtain in K . viminalis t whilst the fruits favour the latter 

 species, as do also the timber and oil. 



