168 



TREES OF NORTH AMERICA 



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 



Fig. 162 



(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. 



VIE. JTJGLANDACE^:. 



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 up- 

 ward, penniveined, sessile, short-stalked or the terminal usually long-stalked. Flowers 

 monoecious, 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 numer- 

 ous 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 ot a 1-3-celled ovary subtended by an in- 

 volucre 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 



