Buttonbush 



843 



bers of this family, it has been superseded by the more reliable Cinchona barks 

 and their alkaloids, although it is very nearly related to them, having been origi- 

 nally described as a species of Cinchona. 



The genus comprises about 20 species, all tropical American; the name is 

 Greek in reference to the long-exserted stamens. Exostema parviflorum L. C. 

 Richard, is the type species. 



III. BUTTONBUSH 



GENUS CEPHALANTHUS LINN^US 

 Species Cephalanthus occidentalis Linnaeus 



SMALL tree or shrub inhabiting swamps and stream banks from New 

 Brunswick to Nebraska, southward to Florida, Texas and northern 

 Mexico; also in Arizona and California; it attains its maximum height 

 of 15 meters, with a trunk diameter of 3 dm. in Arkansas and adja- 

 cent Texas. 



The crooked branches are outspreading, forming a round top. The bark is 

 about 4 mm. thick, fissured, and splits into narrow scales of a dark brown to 

 nearly black color. The twigs are stout, 

 somewhat angular, pithy, light green and 

 smooth, turning brown and glaucous, and 

 finally dark brown. The buds are gen- 

 erally axillary and very inconspicuous. 

 The deciduous leaves are opposite or in 

 whorls, membranous, oblong, lanceolate or 

 ovate, 7 to 20 cm. long, sharp or some- 

 times taper-pointed, tapering, rounded or 

 slightly heart-shaped at the base, dark 

 green and smooth above, paler, sometimes 

 slightly hairy and prominently veined be- 

 neath; the le'af-stalk is stout, 5 to 15 mm. 

 long. The flowers, opening in spring or 

 summer, are perfect, in axillary or termi- 

 nal, solitary or panicled, globose heads 2.5 

 to 5 cm. in diameter, the individual flowers white, in the axils of bracts; the 

 calyx-tube is about 2 mm. long and hairy at the base, the 4 or 5 lobes are short 

 and blunt ; the corolla is funnelform, i cm. long, smooth or hairy, its 4 lobes 

 ovate and blunt; the 4 stamens are inserted on the throat of the corolla, their 

 filaments short, the anthers oblong; the ovary is 2-celled with a solitary ovule in 

 each ceU; the style is filiform, twice the length of the corolla and capped by the 

 stigma. The fruits form a compact globose head 1.5 to 2.5 cm. in diameter; they 

 are crowded, obpyramidal, 7 to 8 mm. long. 



Fig. 766. — Buttonbush. 



