— 51 — 



In connection with the above, reference should be made to an abstract 

 of a paper by de Jong on citronella grass which is published in the 

 Chemist and Druggist 1 ). We have already referred to these investigations 

 by de Jong 2 ) and may now content ourselves with adding a few details 

 to the particulars then communicated. De Jong proposes to call the 

 Maha-Pengiri species, which is chiefly grown in Java, by the name of 

 Andropogon Nardus, Java, and to designate the Lenabatu species, which is 

 typical of Ceylon, A. Nardus, Ceylon ; the former would thus correspond 

 with Cymbopogon Winterianus, Jowitt; the latter with O. Nardus, Rendle, 

 lenabatu. It is true that Maha-Pengiri grass yields more and better oil 

 than does Lenabatu grass, but it requires a richer soil and more careful 

 cultivation than the last-named 3 ). As a rule, the grass is propagated in 

 Java by dividing the old roots, the root-sections being planted so far 

 apart that every new plant has a space of three square feet. No definite 

 rule can be given for the number of grass-crops to be cut in the course 

 of the year, as it varies according to soil and climate. De Jong con- 

 siders it best to cut the grass when the fifth leaf has developed. The 

 distillation is often carried out in Java by superheated steam under a 

 pressure of 3 to 4 atmospheres; this mode of working being more rapid 

 and giving a higher yield, usually varying from 0,5 to 0,9%. It is said 

 to be of advantage to cut up the raw material as small as possible. 



As in the case of Maha-Pengiri grass, de Jong has now also ex- 

 perimented on the oil-content of the leaves of Lenabatu grass in different 

 stages of growth, and has obtained precisely similar results as with the 

 Malia-Pengiri grass. The oil-yield diminishes as the leaf ages and so 

 does the total-geraniol content of the oil. In the oils examined by de Jong 

 this total-geraniol content reached a percentage (from 86% for the first 

 to 75% for the sixth leaf) which had not previously been observed in 

 Lenabatu oil. 



Oil of Citrus Hystrix. An oil has been distilled at Buitenzorg from 

 the peel of Djoeroek Poeroet (Citrus Hystrix, D. C; C. Papedia , Miq., 

 N. O. Rutaceae). The oil-yield was 4%, and the oil possessed the following 

 constants: d 26 o 0,942, «-f-9°. It contained 40% citral 4 ). 



A sample which was handed to us last year by Dr. de Jong of 

 Buitenzorg was evidently identical with the oil described above, but in 

 the meantime it had become greatly resinified, as was shown in the first 

 place by the greatly increased specific gravity: di 5o 0,9654, « D + 7°18 f , 

 "d2oo 1,48277, soluble in its own vol. and more of 80°/ alcohol. The oil 

 was of a pale yellow colour and had an odour resembling that of lemon. 



*) Chemist and Druggist 78 (1911), 20. 



2 ) Report April 1909, 36. 



3 ) Also comp. Report April 1907, 32. 



4 ) Jaarboek van net Departement van Landbouw in Nederlandsch-IndiS, 1909, 64. 



4* 



