46. EUPHORBIACE^.. 



135 



Family 46— EUPHORBIACE>E. 



Flowers unisexual; perianth either absent and replaced 

 by an involucre, or of 3-5 divisions, free or united at base; 

 stamens few or numerous: styles 2-3; fruit capsular, with 

 2-3 carpels (cocci), each containing 1-2 seeds, the carpels 

 separating from each other at maturity, leaving a per- 

 sistant central axis, and usually opening elastically by 2 

 valves. 



Perianth replaced by a calyx-like involucre, 

 containing 1 female and several male 

 flowers of 1 stamen each ; leaves entire 



or toothed 



Male and female flowers distinct ; stamens 

 numerous; leaves palmatifid .- 



Euphorbia 1 



RiciNrs 2 



1. Euphorbia, L. 



Male and female flowers united in a small involucre, 

 shaped like a calyx and presenting the appearance of a 

 single bisexual flower ; involucre campanulate, with 4-5 

 teeth, alternate with as many thick, spreading petaloid 

 glands; stamens 8-15, on jointed filaments, intermixed with 

 membranous bracts and surrounding 1 pedicellate female 

 flower ; styles 3, usually bifid ; capsule hanging out of the 

 involucre and composed of three 1-seeded carpels. Herbs or 

 shrubs containing a bitter milky juice; flowers in umbels, 

 with a whorl of floral leaves at the base of the rays, each 

 ray usually forked several times, with a pair of opposite 

 floral bracts at each fork. 



Stem-leaves opposite, large; capsule large ... 

 Stem-leaves alternate or scattered. 

 Glands crescent-shaped. 

 Annuals. 



Leaves broad, stalked ; carpels 2-keeled 

 Leaves narrow, sessile: carpels scarcely 



keeled 



Perennials; leaves narrow, sessile. 

 Bracts denticulate; carpels smooth ... 

 Bracts entire; carpels tuberculato 

 Glands almost truncate ; umbel of 5-10 

 rays; undershrub 



1. Euphorbia Lathyris, L. Gaper Spurc/e. Glab- 

 rous and glaucous biennial, 1 m. (3 ft.) high or 

 more, with a stout, hollow, erect stem ; leaves oppo- 

 site, in 4 regular rows, oblong-lanceolate, all sessile 

 and entire ; umbel of 2-5 long rays with oval- 

 lanceolate floral bracts; glands crescent-shaped, with 

 short, blunt horns; capsule rather large, smooth; seeds 



E. dendroides 6 



