December, 1910.] 



Solubility in alcohol : gives a clear 

 solution in its own volume of 80 per cent, 

 alcohol, and shows a very slight opal- 

 escence with 10 volumes. 



Remarks. — See remarks uuder Nos. 14 

 and 14a. The yield of oil obtained in this 

 distillation was 059 per cent. This 

 sample is intermediate in quality be- 

 tween Nos. 14 and 14a, and like them re- 

 sembles the Java and Federated Malay 

 States oils rather than Ceylon citronella 

 oil. 



No. 15. 



Quantity : 480 cc. ; distilled June 22 and 

 September 18, 1907. 



Description: Deep yellow oil, possess- 

 ing a distinctly inferior odour. A small 

 deposit was present in the bottle con- 

 taining the oil. 



Results of Examination. 

 Specific gravity at 15715° C = 0-912. 



Optical rotation in 100 mm. tube at 

 21° C = - 1° 38'. 



" Total alcohols " (geraniol and citro- 

 nellal) == 48'6 per cent. 



Geraniol = 25*5 per cent. 



Citronellal _ 231 per cent. 



Solubility in alcohol : gives a clear 

 solution with its own volume of 80 per 

 cent, alcohol, but becomes opalescent and 

 slightly turbid with 10 volumes. 



Remarks.— The grass yielding this oil 

 was supplied to Mr. Jowitt as " maha- 

 pengiri," but turned out to be merely a 



mana" grass. It has been identified by 

 Dr. Stapf as Cymbopoyon Nardus, Rendle, 

 var. Linncei, Stapf (typicus). The oil is 

 very similar in composition to Nos. 2* and 

 11, both belonging to the same group 

 according to Dr. Stapf's identification. 

 The yield in this distillation was 0'25 

 per cent. 



No. 15* 



Quantity : 305 cc. ; distilled August 17, 

 1908. 



Description : Clear, pale yellow oil with 

 a fairly good, rather pungent citronella 

 odour. A slight deposit was present. 



Results of Examination. 



Specific gravity at 15°/15 a C = 0"909. 



Optical rotation in 100 mm. tube at 

 21° = + 2f 18'. 



Geraniol = 35'8 per cent. 



Citronellal = 20*6 per cent. 



495 Oil* and Fats. 



Solubility in alcohol : gives a clear 

 solution with its own volume of 80 per 

 cent, alcohol. With 10 volumes of the 

 alcohol this oil shows only a very slight 

 opalescence. 



Remarks. — This oil is from the same 

 source as No. 15. Tne yield of oil in this 

 distillation was 0"42 percent,, i.e., almost 

 double that obtained in the first distilla- 

 tion. The oil shows a large increase in 

 geraniol and a decrease in citronellal as 

 compared with No. 15. It closely re- 

 sembles in composition Nos. 1** and 9*. 



No. 27*. 



Quantity : 121 cc. : distilled August 28, 

 1908. 



Description : Pale yellow oil with a 

 rather spicy and pungent citronella 

 odour. Practically no deposit was 

 present. 



Results of Examination. 



Specific gravity at 15° /15° C = 0-905^ 



Optical rotation in 100 mm. tube at 

 20° C = —11° 14'. 



"Total alcohols " (geraniol and citro- 

 nellal) = 59'6 per cent. 



Geraniol = 36*0 per cent. 



Citronellal = 23"6 per cent. 



Solubility in alcohol : gives a clear 

 solution with its own volume of 80 per 

 cent, alcohol, and remains quite clear 

 with 10 volumes. 



Remarks. — The grass yielding this oil 

 was supplied to Mr. Jowitt as " maha- 

 pengiri" (C. Winterianus, Jowitt), but 

 m botanical specimen was sent to the 

 Imperial Institute for identification. 

 The above results indicate that the grass 

 more closely resembles " lena-batu-pen- 

 giri" than " maha-pengiri." Compare 

 with Nos. 4 and 12. The yield of oil in 

 this distillation was 0'51 per cent. 



Remarks on the Citronella Oils. 



The citronella oils included in this 

 series of samples belong to three groups, 

 deiived from (a) " Mana " or wild grasses, 

 (b) "Lena-batu" grass, and (c) "Maha- 

 pengiri" or "Winter's grass," and it 

 will be convenient to discuss them under 

 these headings. A table summarizing 

 the results of the examination of the oils 

 is attached below. 



(a) Mana Grass Oils. 



Dr. Stapf has divided the mana grasses 

 into two varieties of Cymbopogon Nar- 

 dus, viz., var. Linncei (typicus) and van 



