".. 



64 per cent, in the fraction, determined by the phosphoric acid method, and 95 

 per cent, distilled below 198 C. It contained phellandrene, and was exceedingly 

 rich in cineol for a phellandrene-bearing oil. 



To enable the investigation to be more complete, material was obtained for 

 distillation of the reputed E. Risdoni var. elata, from Mount Wellington, Tasmania, 

 collected in August, 1912. The results show the oil to be in agreement with those 

 of the ordinary form previously determined. 



Material for distillation of the so-called E. amygdalina var. hyper icifolia, 

 was also obtained by Mr. L. G. Irby, near Hobart, Tasmania, in April, 1912, 

 under the direction of Mr. Rodway. The results with this oil were practically 

 identical with those of E. Risdoni, and as the botanical features were also in 

 agreement with that species, we consider it to be E. Risdoni. The chief 

 characteristics in the oil of E. Risdoni are that it contains over 55 per 

 cent, of cineol when determined by the resorcinol method; a somewhat large 

 amount of phellandrene ; belongs to the "peppermint" group, as it contains 

 some piperitone ; has a somewhat high saponification number by boiling, and a 

 low one by the cold method; gives over 90 per cent, distilling below 195 C., and 

 has scarcely any objectionable volatile aldehydes. Both amyl-alcohol and amyl- 

 acetate were detected. 



The crude oil of E. Risdoni (supposed variety elata) from Mount Wellington, 

 Tasmania, was lemon-yellow in colour, and responded to all the tests and require- 

 ments recorded above. The yield of oil was 1-52 per cent. Specific gravity at 

 15 C. = 0-9061; rotation a D - - 14-1; refractive index at 20 1-4670, and 

 was soluble in 3 volumes 70 per cent, alcohol. The slightly larger amount of 

 phellandrene, and correspondingly less cineol at the time, accounts for the slight 

 differences in rotation, gravity, and solubility, to those previously recorded. 



On rectification, the usual amount of acid water and volatile aldehydes 

 came over below 173 C. (corr.). Between 173-184, 82 per cent, distilled, and 

 between 184-195, n per cent, distilled. These fractions gave results as 

 follows : 



First fraction, sp. gr. at 15 C. :; 0-8995; rotation a D - - 16-6; refractive 



index at 20 = 1-4647. 



Second ,, ,, = 0-9010; rotation a D -- 9-3 ; refractive 



index at 20 1-4619. 



The cineol was determined by the resorcinol method, the result indicating 

 58 per cent, of that constituent in the crude oil. The saponification number 

 for the 'esters and free acid by boiling was 21-3 ; and in the cold, with two hours' 

 contact, 5-5. 



The supposed variety hypericijolia gave a light amber-coloured oil, having 

 a somewhat pleasant odour; the average yield was 1-24 per cent., and the oil 

 agreed in all respects with the requirements for that of E. Risdoni. 



The specific gravity of the crude oil at 15 C. ; : 0-9045; rotation a D - 

 14-6; refractive index at 20 1-4656, and was soluble in 5 volumes 70 per 

 cent, alcohol. The saponification number for the esters and free acid by boiling 

 was 23-8 ; and in the cold, with two hours' contact, 3-9. It is thus evident that 

 the main ester in the oil of E. Risdoni is not geranyl-acetate. 



On rectification, only a few drops of acid water and volatile aldehydes 

 came over below 173 C. (corr.). These aldehydes had no objectionable odour. 

 Between 173-198, 94 per cent, distilled. This had specific gravity at 15 C. = 

 0-8991; rotation D - 15-4. and refractive index at 20 : 1-4637. The com- 

 parative absence of high-boiling constituents is worthy of notice. 



The cineol was determined by the resorcinol method in the large fraction, 

 and calculated for the crude oil; the result was 56 per cent. 



