There are probably one or two indigoes indigenous in America, but ill defined, and often intermixed in cultivation with the species of the old world, and naturalized beyond the limits of cultivation. This interchange makes the matter too uncertain for me to venture upon any researches into their original habitat. Some authors have thought that _I. Anil_, Linnæus, was one of these species. Linnæus, however, says that his plant came from India (_Mantissa_, p. 273). The blue dye of the ancient Mexicans was extracted from a plant which, according to Hernandez’ account,[660] differs widely from the indigoes. +Henna+—_Lawsonia alba_, Lamarck (_Lawsonia inermis_ and _L. spinosa_ of different authors). The custom among Eastern women of staining their nails red with the juice of henna-leaves dates from a remote antiquity, as ancient Egyptian paintings and mummies show. It is difficult to know when and in what country this species was first cultivated to fulfil the requirements of a fashion as absurd as it is persistent, but it may be from a very early epoch, since the inhabitants of Babylon, Nineveh, and the towns of Egypt had gardens. It may be left to scholars to show whether the practice of staining the nails began in Egypt under this or that dynasty, before or after certain relations were established with Eastern nations. It is enough for our purpose to know that _Lawsonia_, a shrub belonging to the order of the Lythraceæ, is more or less wild in the warm regions of Western Asia and of Africa to the north of the equator. I have in my possession specimens from India, Java, Timor, even from China[661] and Nubia, which are not said to be taken from cultivated plants, and others from Guiana and the West Indies, which are doubtless furnished by the imported species. Stocks found it indigenous in Beluchistan.[662] Roxburgh also considered it to be wild on the Coromandel[663] coast, and Thwaites[664] mentions it in Ceylon in a manner which seems to show that it is wild there. Clarke[665] says, “very common, and cultivated in India, perhaps wild in the eastern part.” It is possible that it spread into India from its original home, as into Amboyna[666] in the seventeenth century, and perhaps more recently into the West Indies,[667] in the wake of cultivation; for the plant is valued for the scent of its flowers, as well as for the dye, and is easily propagated by seed. There is the same doubt as to whether it is indigenous in Persia, Arabia, and Egypt (an essentially cultivated country), in Nubia, and even in Guinea, where specimens have been gathered.[668] It is even possible that the area of this shrub extends from India to Nubia. Such a wide geographical distribution is, however, always somewhat rare. The common names may furnish some indication.