The family consists of a single genus, Leitneria Chapm., with one species of the southern United States, named for a German naturalist killed in Florida during the Seminole War.
1. [Leitneria floridana] Chapm. Cork Wood.
Leaves 4′—6′ long, 1½′—2½′ wide, with petioles 1′—2′ in length. Flowers opening at the end of February or early in March; staminate aments 1′—1¼′ long, ¼′ thick, and twice as long as the pistillate. Fruit solitary or in clusters of 2—4, ripening when the leaves are about half grown, ¾′ long, ¼′ wide.
A shrub or small tree, occasionally 20° high, with a slender straight trunk 4′—5′ in diameter above the swollen gradually tapering base, spreading branches forming a loose open head, and branchlets at first light reddish brown and thickly coated with gradually deciduous hairs, becoming in their first winter glabrous or puberulous, especially toward the ends, and dark red-brown. Winter-buds: terminal broad, conic, ⅛′ long, covered by 10 or 12 oblong nearly triangular closely imbricated scales coated with pale tomentum and long-persistent at the base of the branch; lateral scattered, ovoid, flattened. Bark about 1/16′ thick, dark gray faintly tinged with brown, divided by shallow fissures into narrow rounded ridges. Wood soft, exceedingly light, close-grained, the layers of annual growth hardly distinguishable, pale yellow, without trace of heartwood; occasionally used for the floats of fishing-nets.
Distribution. Borders of swamps of the lower Altamaha River, Georgia (C. L. Boynton); muddy saline shores on the coast of the Gulf of Mexico near Apalachicola, Florida; swampy prairies, Velasco (E. J. Palmer), and swamps of the Brazos River near Columbia, Brazoria County, Texas; Varner, Lincoln County (B. F. Bush), and Moark, Clay County (E. J. Palmer) Arkansas; and in Butler and Dunklin Counties, southeastern Missouri, here sometimes occupying muddy sloughs of considerable extent to the exclusion of other woody plants.
VIII. JUGLANDACEÆ.
Aromatic trees, with watery juice, terete branchlets, scaly buds, the lateral buds often superposed, 2—4 together, and alternate unequally pinnate deciduous leaves with elongated grooved petioles and without stipules, the leaflets increasing in size from the lowest upward, penniveined, sessile, short-stalked or the terminal usually long-stalked. Flowers monœcious, opening after the unfolding of the leaves, the staminate in lateral aments and composed of a 3—6-lobed calyx in the axil of and adnate to an ovate acute bract, and numerous stamens inserted on the inner and lower face of the calyx in 2 or several rows, with short distinct filaments and oblong anthers opening longitudinally; the pistillate in a spike terminal on a branch of the year and composed of a 1—3-celled ovary subtended by an involucre free toward the apex and formed by the union of an anterior bract and 2 lateral bractlets, a 1 or 4-lobed calyx inserted on the ovary, a short style with 2 plumose stigmas stigmatic on the inner face, and a solitary erect orthotropous ovule. Fruit drupaceous, the exocarp (husk) indehiscent or 4-valved, inclosing a thick- or thin-shelled nut divided by partitions extending inward from the shell, and like the shell more or less penetrated by internal longitudinal cavities often filled with dry powder. Seed solitary, 2-lobed from the apex nearly to the middle, light brown, its coat thin, of 2 layers, without albumen; cotyledons fleshy and oily, sinuose or corrugated, 2-lobed; radicle short, superior, filling the apex of the nut. Of the six genera of the Walnut family two occur in North America.
CONSPECTUS OF THE NORTH AMERICAN GENERA.
Aments of staminate flowers simple; husk of the fruit indehiscent; nut sculptured; pith in plates.1. [Juglans.] Aments of staminate flowers branched; husk of the fruit 4-valved; nut not sculptured; pith solid.2. [Carya.]