EUPHORBIACE^ 595 



ovules 1 or 2 in each cell, suspended, anatropous ; raphe ventral ; micropyle 

 superior. Fruit a drupe or capsule. Seeds albuminous ; cotyledons flat, much 

 longer than the superior radicle. 



The Euphorbia family, widely distributed over the tropical and temperate 

 regions, with some one hundred and thirty genera and over three thousand 

 species, is represented in the United States by three arborescent genera, with 

 only five species, and by many shrubby herbaceous and annual plants. 



CONSPECTUS OF THE ARBORESCENT GENERA OF THE UNITED STATES. 



Fruit drupaceous. 



Nutlets usually 1-celled and 1-seeded ; stamens as many or twice as many as the calyx- 

 lobes, free. 1. Drypetes. 

 Nutlets 6-S-celled and 6-8-seeded ; stamens 2 or 3, united into a column. 



2. Hippomane. 

 Fruit a 3-lobed capsule splitting into 3 2-valved 1-seeded carpels. 3. Gymnanthes. 



1. DRYPETES, Vahl. 



Trees or shrubs, with thick juice, and terete branchlets. Leaves involute in the 

 bud, petiolate, penniveiued, coriaceous, persistent; stipules minute, caducous. 

 Flowers axillary, sessile or pedicellate, their pedicels from the axils of minute decidu- 

 ous bracts, ebracteolate, the males in many-flowered clusters, the females solitary or 

 in few-flowered clusters; calyx divided nearly to the base into 4 or 5 lobes rounded 

 or acute at the apex, deciduous or persistent under the fruit; stamens inserted under 

 the margin of a flat or concave slightly lobed disk, in the pistillate flower; filaments 

 filiform; anthers ovate, emarginate, attached on the back near the base, extrorse 

 or introrse, 2-celled, the cells affixed to a broad oblong connective; ovary sessile, 

 ovoid, 1 or rarely 2-celled, with 1 or 2 sessile or subsessile peltate or reniform stig- 

 mas, rudimentary or wanting in the staminate flower; ovules collateral, descending, 

 attached to the central angle of the cell, operculate, with a hood-like body developed 

 from the placenta. Fruit drupaceous, ovoid or subglobose, tipped with the withered 

 remnants of the stigmas; flesh thick and corky or thin and crustaceous; stone thick 

 or thin, bony or crustaceous, 1-celled and 1-seeded, or rarely 2-celled and 2-seeded. 

 Seed filling the cavity of the nut; seed-coat crustaceous or membranaceous; embryo 

 erect in thin fleshy albumen. 



Drypetes is confined to the tropical regions of the New World, and is distributed 

 from southern Florida through the West Indies to eastern Brazil. Of the eleven 

 species now distinguished, two inhabit the coast of southern Florida. 



The generic name, from Spvirna, relates to the character of the fruit. 



CONSPECTUS OF THE NORTH AMERICAN SPECIES. 



Calyx 5-lobed ; stamens 8 ; ovary 1-celled ; fruit oblong ; outer coat thick and mealy ; 



stone thick-walled. 1. D. Keyensis (D). 



Calyx 4-lobed ; stamens 4 ; ovary 2-eelled ; fruit subglobose ; outer coat thin, crustaceous ; 



stone thin-walled. 2. D. lateriflora (D). 



1. Drypetes Keyensis, Urb. "White "Wood. 



Leaves appearing in early spring and falling during the second year, entire, oval 

 or oblong, often more or less falcate, acute, acuminate, rounded or rarely emarginate 

 at the apex, rounded or wedge-shaped at the base, when they unfold thin and mem- 



