ARISTOLOCHIA, a genus of shrubs or herbs of the family Aristolochiaceae, often with climbing stems, found chiefly in the tropics. The flower forms a tube inflated at the base. The name (Gr. apcaros, best; Xoxeia, child-birth) alludes to its repute in aiding parturition. The birthwort (A. Clematitis) is a central and south European species, found sometimes in England, apparently wild, on ruins and similar places, but not native. In the United States it has become naturalized along roadsides and in thickets from New York to Maryland. The Dutchman's pipe or pipe vine (A. snacrophylla), native to rich woods in the eastern United States from Pennsylvania to Minnesota and south to Georgia and Kansas, is a vigorous climber widely planted in Europe and the United States as a porch-vine. The flower is of an odd shape and bent like a pipe. Some ro other species are native to the United States. Among the best known of these are the Virginia snake root (A. Serpentaria), called also sangree-root and serpentary, found in dry woods from Connecticut to Michigan and southward to Florida and Louisiana, and valued medicinally for its aromatic stimulant root; the woolly pipe vine (A. tomentosa), native to woods from North Carolina to Missouri and southward; and the western Dutchman's pipe (A. californica), native to California. Among the various species grown in greenhouses are the remark able pelican-flower (A. grandiflora), a native of tropical America, some varieties of which bear immense flowers often 20 in. across with a tail-like appendage 3 ft. or more long; and the showy cal ico-flower (A. elegans), native to Brazil, a graceful, free-blooming climber with solitary flowers having a yellow-green tube 1 in. long and a purple and white blotched limb 3 in. across.