The wonderful fragrance of the March violet is due to an essential oil which it is, however, difficult to extract. For this reason genuine perfume of violets, really prepared from the flowers, is among the most expensive odors, and the high-priced so-called violet perfumes are generally mixtures of other fine odors, while the cheaper grades are made from orris root. VOLKAMERIA. This plant, Volkameria inermis, often cultivated in conservatories, has a very agreeable odor. The perfume called by this name, however, is not obtained from the plant, but is produced by the mixture of several aromatic extracts from other plants. WALLFLOWER. _Latin_—Cheiranthus Cheiri; _French_—Giroflé; _German_—Levkojenblüthen, Goldlack. The wallflower, a well-known biennial garden plant belonging to the Order of Cruciferæ, according to recent experiments yields a very fine odor to certain substances and may be employed in the manufacture of quite superior perfumes. The preparations usually sold as wallflower, however, are not made from the flowers of this plant, but are mixtures of different odors. WINTERGREEN. _Latin_—Gaultheria procumbens; _French_—Gaulthérie; _German_—Wintergrünblätter. This herbaceous plant, indigenous to North America, especially Canada and the Northern and Middle United States, where it grows wild in large quantities, has a very pleasant odor due to an essential oil and a compound ether which can also be produced artificially. The odor of wintergreen serves chiefly for scenting fine soaps. YLANG-YLANG. This plant, Unona odoratissima, indigenous to the Philippine Islands, contains an exceedingly fragrant oil. It is brought into commerce from Manilla. * * * * * Owing to climatic relations, it is impossible for the perfumer to procure all the above-enumerated substances in the fresh state; many of them he is forced to purchase through the drug trade, and he should bear in mind to give the preference always to the freshest obtainable goods. At times it is not possible to utilize the materials at once for the extraction of the odors and they must be kept for some time. The vegetable substances should always be stored in an airy, not over dry room; and the material should be often inspected. If a trace of mouldiness shows itself, the material must be worked at once, since, if the mould is allowed to go on, the fragrance will suffer and may be destroyed altogether.