JOURNAL OF THE ARNOLD ARBORETUM THE GENERA OF VALERIANACEAE AND DIPSACACEAE IN THE SOUTHEASTERN UNITED STATES 1 I. K. FERGUSON VALERIANACEAE Batsch, Tab. Affin. Reg. Veg. 227. 1802, nom. cons. (VALERIAN FAMILY) Annual or perennial herbs, sometimes woody at base. Leaves in basalrosettes or opposite, pinnately divided or entire, exstipulate, the basesoften sheathing. Inflorescence a monochasium, thyrse, or many-floweredcompound dichasial cyme, sometimes condensed and capitate, bracteateand bracteolate [ebracteolate]. Flowers irregular or almost regular, bi-sexual or unisexual. Calyx obsolete or developing late and becoming con-spicuous only in fruit, annular [or toothed], adnate to ovary. Corollatubular, 5 [3 or 4]-lobed, imbricate, often basally spurred or saccate[bilabiate]. Stamens epipetalous and alternate with the corolla lobes, vary-ing in number, usually 3 in our genera [1, 2, 3, or 4]; anthers versatile,2-or 4-lobed, 4-locular, introrse, dehiscing longitudinally; pollen tricolpate,echinate. Gynoecium syncarpous, ovary inferior, 3-locular, with twolocules usually suppressed and one fertile, with a solitary, pendulous, an-atropous ovule; style 1, stigma simple or lobed. Fruit dry, indehiscent, thecalyx often developing into a winged, awned, or plumose pappus. Seed 1;endosperm absent; embryo large, straight, the cotyledons oblong, theradicle superior. TYPE GENUS: Valeriana L. A family of about ten genera and 370-400 species, widely distributed but occurring mainly in the North Temperate regions and absent from Australasia; three genera native and one introduced in North America; two genera in our area. Valerianaceae are a natural family closely related to Dipsacaceae but 1 Prepared for a generic flora of the southeastern United States, a joint project of the Arnold Arboretum and the Gray Herbarium of Harvard University made possible through the support of George R. Cooley and the National Science Foundation and under the direction of Carroll E. Wood, Jr., and Reed C. Rollins. This treatment follows the pattern established in the first paper in the series (Jour. Arnold Arb. 39: 296-346. 1958) and continued through those in volumes 40-46 (1959-1965). The area covered is bounded by and includes North Carolina, Tennessee, Arkansas, and Louisiana. The descriptions are based primarily on the plants of this area, with any supplementary material in brackets. References which the author has not seen are marked by an asterisk. The author is indebted to Dr. Wood for his aid and valuable criticisms; to Dr. George K. Brizicky, for his guidance and suggestions; and to Mrs. Gordon W. Dillon, for her help in the preparation of the typescript.[VOL. 46218
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