Sex. Syst. Monandria, Monogynia.
The root of this plant is "perennial, tuberous, furnished with long, white, fleshy fibres, and jointed like ginger, but much larger; when fresh, of a deep yellow; possessing a strong, not very agreeable, camphoraceous smell, and warm, spicy, bitterish taste," (Roxburgh.) Sir Joseph Banks and Dr. Comb (to whom specimens of it were given) thought that it was the true cassumunar of the shops. [Roxburgh, Asiatic Researches, vol. xi.] But the great resemblance of cassumunar root to round zedoary leads me to think that it is obtained from a species of Curcuma.
About the year 1672, Dr. Pechey received from his brother, factor to the East India Company, a root which was called cassumunar (variously spelt casmunar, casumunar, &c), rysagone (or risagon), and bengale (or bengalle). [Pechey, Some Observations made on the Root Cassumuniar, called otherwise Rysagone, imported from the East Indies [MS. without date, in the library of the Royal Medical and Chirurgical Society of London]; Sir Hans Sloane, Phil. Trans. No. 284, p. 580.] These names were probably fictitious, and were merely given to conceal the secret of its nature.
This root is still found in the warehouses of some London druggists, who call it cassumunar root (radix cassumunar), and consider it to be identical with zerumbet root (see Curcuma Zedoaria). It appears to me to be the turmeric-coloured zedoary of Ainslie, the zedoaria radice lutea of Breynius, [Prodromus, ii. 105.] the tommon besaar or tommon lawac of Rumphius. [Herb. Amboyn. pars 5ta, p. 168.] It occurs in segments (halves or quarters) of an ovate tuber (which in the dried state must have been about the size of a pigeon's egg), the external surface of which is marked with circular rings and the bases of the root fibres, and is of a dirty turmeric-yellow colour. Internally it is reddish-brown, and has some resemblance, in its colour and pellucidity, to a fresh-fractured surface of Socotrine aloes. Its flavour is warm and aromatic; its odour is somewhat like that of turmeric. It has not been analyzed. Its effects must be similar to those of zedoary and ginger. It was at one time used in convulsive and other cerebral diseases, [Some Observations made upon the Root called Casmunar, imported from the East Indies, published by a Doctor of Physic [Dr. Pechey?] in Gloucestershire. London, reprinted in the year 1603.] but has fallen into disuse.
The Elements of Materia Medica and Therapeutics, Vol. II, 3th American ed., was written by Jonathan Pereira in 1853.