The volatile oil commonly known as Indian-Grass Oil, is supposed by Professor Royle to be produced from a peculiar species of Andropogon. This species he considers identical with the Καλαμος αςωματιχος of the ancient Greeks, an he has therefore called it A. calamus aromaticus.

For the specimen of the oil which I have examined I am indebted to Dr Christison, by whom it was received from Mr Key, of the Madras Medical Service. This gentleman obtained it while resident in the Nizam's territories, not far from Ellichpoor, where the plant grows freely on hilly ground. The oil is there called Roossah-oil.