481 



It is botanically and chemically described in our work, 

 "Eucalypts and their Essential Oils," under the name of 

 E. Cambagei, p. 113. 



23. Eucalyptus acervula, Hook. f. (Fl. Tas.). 



This species of Hooker was fully investigated by us when 

 writing our paper on "The Eucalypts of Tasmania" (Proc. 

 Roy. Soc. Tas., October, 1912), where it is also shown in 

 what respects it differs from E . paludosa of New South Wales. 

 It is the species recorded by botanists of South Australia as 

 ]\ . (J a ii it ii, and is figured as such by J. E. Brown in his 

 "Forest Flora of South Australia." E. Ginuiii, the "Cider 

 tree" of Tasmania is, however, quite another species, the 

 botanical and chemical differences being already given by us 

 (Joe. cit.J. Both botanically and chemically the relationship is 

 complete between the South Australian and Tasmanian trees. 

 It is thus shown that E. acervula is not endemic in Tasmania, 

 as was previously supposed. Mr. J. H. Maiden, in his 

 "Critical Revision of the Genus Eucalypts," vol. iii., part 7, 

 p. 133, synonymizes this species under E. ovata, Labillardiere, 

 a synonymy with which we cannot agree, as the evidence 

 advanced appears to us altogether insufficient, and Labil- 

 lardicre's plate and description do not match the E. acervvla 

 of Tasmania and South Australia. 



Essential Oil. 



Leaves and terminal branchlets of this species were 

 received for distillation from the Conservator of Forests 

 of South Australia, Mr. Walter Gill, in the month of 

 December. 



The crude oil was somewhat viscid, and had an aromatic 

 odour. It evidently consisted largely of high-boiling con- 

 stituents, such as sesquiterpene : it was dark coloured, 

 and a phenol was present in fair amount for a Eucalyptus oil. 

 A solid paraffin was also present. Phellandrene was absent, 

 and cineol was present only in small amount. The ester 

 content was somewhat high, the saponification number for the 

 esters and free acids, in the cold with alcoholic potash, being- 

 40'7. The separated oil had a marked odour of geraniol, so 

 that the principle ester consisted of geranyl-acetate. The 

 amount of this ester in the oil of this South Australian tree 

 may thus be stated to be 14 per cent. Geranyl-acetate has 

 been isolated from the oils of several Eucalyptus species, and 

 in one instance (E. Macartli uri ) over 70 per cent, of this 

 ester has been found. 

 Q 



