— 53 — 



Eucalyptus citriodora gives an oil very rich in citronellal (about 90%) 

 in a yield of 0,58 °/ . 



The most numerous species are those which yield oils containing 

 eucalyptol. For the production of such oils, E. Globulus and E. Smithii 

 come chiefly under consideration; the former yields about 0,75 °/ and 

 the latter 1,5 to 2°/ oil, undoubtedly the best tree which is to be 

 preferred for cultivation. 



In an experiment with regard to the duration of the distillation, 

 Smith found that 89°/ of the whole distillate passed over within 

 the first 2 hours, 7°/o m tne third hour, and 4°/ in the fourth. It 

 may be accepted that in the first 2 hours the entire quantity of 

 eucalyptol distils over, whilst the less volatile substances, sesquiter- 

 penes, etc. remain behind. 



Of volatile acids in the free state, only acetic acid was detected 

 in eucalyptus oils. In the distillation water oi Eucalyptus amy gdalina, 

 methyl, ethyl, isobutyl, and amyl alcohols were detected. The latter, 

 esterified with eudesmic acid, is present in large quantity (about 57%) 

 in the oil of E. aggregata 1 ). Other constituents of the eucalyptus oils 

 worth mentioning are: eudesmol in E. camphor a, aromadendral in 

 E. salubris, piperitone in E. piperita, and sesquiterpenes in various 

 species, especially in E. haemastoma up to above $o°/ . 



As a continuation of J. H. Maiden's work: "A critical revision 

 of the genus Eucalyptus" 2 ), the eighth 3 ) part has now appeared, which 

 forms a worthy addition to the previous parts, both in point of execution 

 and get-up. In this number the following species are described in detail : 

 Eucalyptus capitellata Sm. [Synonyms: E. congesta R. Br., E. ca- 

 pitellata Sm., var. (?) latifolia Benth., E. Baxteri R. Br. and E. santali- 

 folia F. v. M. var. (?) Baxteri Benth.]. 



Eucalyptus Muelleriana Howitt. 



Eucalyptus macrorrhyncha F. v. M. [Synonyms: Var. (?) brachycorys 

 Benth., E. scyphoidea Naudin]. 



Eucalyptus eugenioides Sieb. [Synonyms: E. scabra Dum-Cours, 

 E. penicillata Hort, E. acervula Sieb., E. oblonga D. C, E. undulata (?) 

 Tausch., var. nana Deane and Maiden, E. oleifolia A. Cunn., E. ligustrina 

 D. C. (E. salicifolia Cav.)]. 



Eucalyptus marginata Sm. [Synonyms : E. pedicellata R. Br., E. flori- 

 bunda Hiigel, E. hypoleuca Schauer, E. Mahogani F. v. M.]. 



Eucalyptus buprestium F. v. M. 



Eucalyptus sepidcralis F. v. M. 



*) Comp. Report April 1901, 33. 



2 ) Comp. Report October 1903, 37; October 1904, 39; April 1905, 37; 

 October 1905, 33 and April 1906, 35. 



3 ) Sydney 1907. 



