MADDER (AS. mwdere, mwddre, Icel. mapra, madder). Rubio. A genus of plants of the flat, ural order Itubiacele, very nearly allied to the genus Galium or bed-straw (q.v.), and differing from it chiefly in having a juicy fruit resembling two small berries growing together. The species are found in the tropical and warmer temperate parts, both of the Old and thu New World, and are important for the coloring matter of their roots. The most important is the common madder or dyer's madder (Rubia tinelorum), a native, probably, of the south of Europe as well as of Asia and now' cultivated in most European coun tries, and also in the East Indies, China, etc. It is a perennial, with weak stems and whorls of 4-6 elliptic or lanceolate glossy leaves, the stem and leaves rough with sharp prickles; small greenish-yellow flowers, and black fruit. The Turkish madder (Li:or( or A lizari) was probably the earliest in use, but the French variety grown in the vicinity of Avignon, is now considered the best. In the Levant the plants are plucked when
five or six years old; but in Europe they are al lowed to grow only two or three years. The best quality, known as crop-madder, is that which is freed from the brown outer crust before grinding. Mull-madder, the most impure variety, is ob tained by grinding rootlets, the woody parts of the root, brown outer crust, and all. From the madder-roots are also prepared. by fermentation and filtration of the separated dye-eolors, the eommercial extracts known as madder-flowers and gurancinc. The importance of madder and madder preparations has almost entirely disap peared with the development of the artificial manufacture of alizarin. Consult Sadtler. In dustrial Organic Chemistry (Philadelphia, 1900 ) . See ALIZARIN.