Among the garden plants, the most odoriferous are the dry ones, such as rue, mint, and parsley, as also those which grow on dry soils. Some fruits become more odoriferous the older they are, the quince, for example, which has also a stronger smell when gathered than while upon the tree. Some plants, again, have no smell but when broken asunder, or when bruised, and others only when they are stripped of their bark. Certain vegetable substances, too, only give out a smell when subjected to the action of fire, such as frankincense and myrrh, for example. All flowers are more bitter to the taste when bruised than when left untouched.[1976] Some plants preserve their smell a longer time when dried, the melilote, for example; others, again, make the place itself more odoriferous where they grow, the iris[1977] for instance, which will even render the whole of a tree odoriferous, the roots of which it may happen to have touched. The hesperis[1978] has a more powerful odour at night, a property to which it owes its name. Among the animals, we find none that are odoriferous, unless, indeed, we are inclined to put faith in what has been said about the panther.[1979] CHAP. 19.—THE IRIS. There is still another distinction, which ought not to be omitted,—the fact, that many of the odoriferous plants never[1980] enter into the composition of garlands, the iris[1981] and the saliunca, for example, although, both of them, of a most exquisite odour. In the iris, it is the root[1982] only that is held in esteem, it being extensively employed in perfumery and medicine. The iris of the finest quality is that found in Illyricum,[1983] and in that country, even, not in the maritime parts of it, but in the forests on the banks of the river Drilon[1984] and near Narona. The next best is that of Macedonia,[1985] the plant being extremely elongated, white, and thin. The iris of Africa[1986] occupies the third rank, being the largest of them all, and of an extremely bitter taste. The iris of Illyricum comprehends two varieties—one of which is the raphanitis, so called from its resemblance to the radish,[1987] of a somewhat red colour, and superior[1988] in quality to the other, which is known as the “rhizotomus.” The best kind of iris is that which produces sneezing[1989] when handled. The stem of this plant is a cubit in length, and erect, the flower being of various colours, like the rainbow, to which circumstance it is indebted for its name. The iris, too, of Pisidia[1990] is far from being held in disesteem. Persons[1991] who intend taking up the iris, drench the ground about it some three months before with hydromel, as though a sort of atonement offered to appease the earth; with the point of a sword, too, they trace three circles round it, and the moment they gather it, they lift it up towards the heavens.