225 



of the Buiteizorg Botanical Gardens. Sadebeck ("Die Culturge- 

 wachse der Dsutschen Coloaien," Jena, 1899, 247) states that An- 

 dropogon Schooianthus, Linn., is cultivated in some parts of East Africa 

 and the " fragrant lemon-grass oil" distilled from it is used for ad- 

 ulterating rose oil. A. Schcenanthiis, Linn., is a variable plant and is 

 sometimes with difficulty distinguished from A. Nardiis, Linn., 

 botanically (Henry Trimen, " Handbook of the Flora of Ceylon," 

 1900, V. 242), except by the deep groove in the centre of the glume 

 of the bisexual spikelets, which, however, is sometimes obscure, or 

 even absent. It's, vslt. versicolor {Hdickel, Monogr, Androp." [1889] 

 610), however, differs (in Ceylon) from A. Nardus in the longer 

 spikelets, though the spikelets vary so much in the different parts of 

 the spike as to require a very long botanical description, and even 

 this (ibid 241) does not cover intermediate forms, which include 

 some with very broad cordate and amplexicaul bases of the leaves. 

 Variations in odour and in physical properties of perfectly 

 genuine grass oils are attributable not only to the species yielding 

 them, but also to the fact of some of the plants being sub-species, 

 varieties, and forms, and these states have become more or less 

 permanent by cultivation and by change of climate and soil. Such 

 differences in odour and physical properties have also been 

 observed in oils distilled from plants cut in the autumn and in the 

 early stages of growth — especially so with citronella. 



CITRONELLA GRASS. 



In Ceylon there are two forms of the plant— the wild and the 

 cultivated; the former is called "Maana grass" of the patauas. 

 (The patanas are immense tracts of uncultivated land in the interior 

 of the island, up to 5,000 feet above the sea. They are mostly in 

 the Province of Ura, and are covered with grass and scrub. They 

 are partly the result of a destructive method of cultivation formerly 

 permitted, called cheiia, which consists in clearing and burning 

 jungle and raising crops for two or three years on the area cleared.) 

 This plant is the Audropogon Nardus, Linn., var. nilagiricus, Hackel 

 ("Monographic Andropogonese"), who states in " Monographise 

 Phanerogamarum Prodromi" (ed. A. et C. De Candolle, 1 889, vi. 

 604) it to be indigenous on the Nilgiri Mountains. Its spikelets 

 are larger than in the cultivated form, and the glume of the sessile 

 spikelet is sometimes, but rarely, depressed in the central line, or 

 it presents the appearance of a shallow pit. 



The other form of citronella is only known in Ceylon in the 

 cultivated state, and is locally called " Pangiri Maana." The only 

 specimen in the Paradeniya Herbarium is so labelled by Dr. Trimen, 

 and with the words, " Cultivated for citronella oil near Deyandera 

 and Mawendelle, S. Prov." It is a tall, robust plant, with broader 

 leaves than the wild plant " Maana," and has an effuse panicle 

 with zigzag branches, divaricate bracts, smaller spikelets, and no 

 well developed awn. It is the A. Nardus, sub-species geiiuinus of 

 Hackel (loc. cit. 602), referred to by Hooker fil. (" Flor. Brit. Ind." 



