6 inches long, membraneous, on a petiole of about i inch long; venation not 

 prominent, intramarginal vein removed from the edge, lateral veins oblique, 

 spreading. Flowers very numerous, up to thirty, on axillary peduncles. Calyx 

 tube turbinate, or truncate spherical, small, i line long, tapering to a long filiform 

 pedicel ; operculum obtuse. 



Fruit. Numerous, small, pilular, on filiform pedi- 

 cels ; rim thin, contracted ; valves not 

 exserted ; 2, rarely 3, lines in diameter. 



A fruit with little variation in shape and often more 

 globular than depicted here. 



Habitat.- On river banks and mountain ranges of the qpast 

 district, but preferring banks of creeks, New South 

 Wales. 



REMARKS. -This Eucalyptus has had a " battleclore-and -shuttlecock " experience at the hands of systematists 

 since its naming bySieber in " De Candollt's Prodromus," iii, 218, 1828. Bentham, B.Fl., iii, p. 203, gives, its 

 varietal rank under E. amygdaliiia. Labill., and Mueller, in " Kucalyptographia," synonymises it altogether 

 under that species. This action Dr. Woolls strongly opposed, for he states ("Flora of Australia," p. 239) : " No 

 one who has had an opportunity of examining both trees in a living state would suppose them to be allied, as they 

 vary so much from each other in bark and habit," and to this we would add morphological and physical properties. 

 Next Deane and Maiden also place it as a variety of K. amvgdalina, Proc. Linn. Soc., N.S.W., Vol. 20, p. 603. Maiden 

 later, however, synonymises it under E. amygdalina, " A Critical Rev.," Vol. I, p. 151, but restores it to specific 

 rank (Proc. Roy. Soc. N.S.W., Vol. 51, p. 461), placing our E. Australiana as a synonym. Dr. Woolls was familial 

 with the tree in the field under the common name of " River White Gum," and Bentham reproduces this name for 

 it under Woolls' authority. Sieber travelled where the " River White Gum " now occurs, and the attempt made to place 

 E. Australiana as Sieber's tree is difficult to understand, as there is nothing to show that that author ever travelled 

 into what was in 1834 remote and inaccessible parts of the Colony, and so the chances are all in favour that he never 

 saw this latter tree, as it is only within the last few years that the district has been opened up ; and, besides, Sieber's 

 description does not match E. A ustraliana, but it does match what has been known ami is still recognised as the ' ' River 

 White Gum" of Woolls. Sieber's E. radiata is acknowledged in our first edition, and no new data appear to us to 

 have been brought to light to warrant our placing E. Australiana, which has a Peppermint bark, as a synonym of 

 this smooth bark tree^ now Maiden's E. numerosa. (Proc. Roy. Soc., N.S.W., Vol. LI). Sieber's E. radiata we 

 regard as (he " River White Gum." 



ESSENTIAL OIL. Leaves and terminal branchlets for distillation were 

 obtained from Monga, N.S.W., in September, 1898. The yield of oil was 1-88 

 per cent. The crude oil was almost colourless, and had a peppermint odour 

 due to the presence of piperitone. It contained much phellandrene, but pinene 

 was only detected in small amount. Only a very small quantity of cineol was 

 found in the portion distilling at near the boiling point of that constituent. 



A close agreement is noticeable between the oil of this species and that 

 of E. dives, the only apparent differences being that the pinene was more pro- 

 nounced in the oil of E. radiata than in that of E. dives, and contained less piperi- 

 tone, consequently the oil commenced to distil at a lower temperature. Esters 

 were not pronounced, and crystallised eudesmol was not detected. 



The crude oil had specific gravity at 15 C. = 0-8747 ', rotation a D 65-1 ; 

 refractive index at 20 = i'48o6, and was insoluble in 10 volumes 80 per cent, 

 alcohol. The saponification number for the esters and free acid was 4-4. 



On rectification, 2 per cent, distilled below 162 C. (corr.). Between 

 162-183, 58 per cent, distilled; between 183-204, 22 per cent, came over, and 

 between 204-235, 13 per cent, distilled. These fractions gave the following 

 results : 



First fraction, sp. gr. at 15 C. - 0-8546 ; rotation a D 71-4. 



Second =0-8677; a D 56-5. 



Third =0-9200; D --i-7, 



