714 EUPHORBIACEAE 



at the oblique base, short-petioled : involucres turbinate-campanulate, villous, barely 

 2 mm. high, sessile or nearly so : glands bearing very irregular reddish or magenta 

 toothed appendages, 2 of them nearly as long as the body of the involucre : capsules ovoid- 

 globose, about 1 mm. long, minutely pubescent : seeds oblong-ovoid, 0.6 mm. long, with 

 strong transverse wrinkles. 



In sand, southern peninsular Florida and tropical America. Spring to winter. 



39. Chamaesyce stictospora (Engelm.) Small. Annual, yellowish green, pilose 

 throughout. Stem branched at the base, the branches ascending or radiating, 5-30 cm. 

 long : leaves numerous ; blades oblong to suborbicular, 4-6 mm. long, obtuse, dentate-ser- 

 rate at the apex, short-petioled, the bases truncate or subcordate ; stipules fringed : invo- 

 lucres clustered, campanulate, 1 mm. high : glands 4, cup-shaped ; appendages rather 

 inconspicuous, crenate, some of them irregular or obsolete : peduncles at length longer than 

 the involucres : capsules ovoid, 1-2 mm. in diameter: seeds narrowly ovoid, 1.2-1. 5mm. 

 long, pointed, pitted, gray or ash-colored, sharply 4-angled. [Euphorbia stictospora 

 Engelm.] 



On prairies, Kansas and Colorado to Mexico. Spring to fall. A Texan variety, with less pubescent 

 foliage, broader and more strongly nerved leaf-blades smaller and broader seeds and narrower append- 

 ages to the glands of the involucre, is C. stictospora Guadaluptnsis Small. [Euphorbia stictospora var. Tex- 

 ensis Millsp., not Euphorbia Tcxana Boiss.l 



40. Chamaesyce adendptera (Bertol.) Small. Annual, closely villous. Stems 

 branched at the base, the branches decumbent or prostrate, 0.5-1.5 dm. long, simple or 

 forking : leaves numerous, approximate or nearly contiguous, blades oblong or ovate- 

 oblong, 4-8 mm. long, acute or acutish, serrulate, very oblique at the base, short-petioled : 

 involucres about 1 mm. high, campanulate or turbinate-campanulate, densely pubescent : 

 glands minute ; appendages white or rose, 2 often much longer than the others, oblique, 

 toothed: capsules 1.5 mm. long, densely pubescent, the angles sharp: seeds about 1 mm. 

 long, oblong, 4-angled, the faces transversely wrinkled. [Euphorbia adenoptera Bertol.] 



In pine lands, Florida and tropical America. Spring to winter. 



41. Chamaesyce pilulffera ( L. ) Small. Annual, pubescent. Stems usually branched 

 at the base, the branches ascending or prostrate, 1-4 dm. long, forking or simple : leaf- 

 blades oblong to oblong-lanceolate, 1-2.5 cm. long, acute, finely serrate, blotched in the 

 middle, oblique, manifestly petioled : involucres in dense short-stalked clusters, turbinate, 

 less than 1 mm. high: glands minute, 0.2 mm. broad; appendages obsolete: capsules 

 little over 1 mm. broad, pubescent : seeds 0.9 mm. long, the faces slightly wrinkled trans- 

 versely. [Euphorbia pilulifera L.] 



In sand, Florida to Texas, New Mexico and tropical America. Also in the tropics generally. 

 Spring to winter. The small form with closely prostrate branches and leaves commonly about 1 cm. 

 long, is C. pilultfera procumbens (Boiss.) Small. [E. pilulifera var. procumbent Boiss.] 



24. ZYGOPHYLLIDITTM Small. 



Annual herbs, with erect forking stems. Leaves opposite or rarely alternate on the 

 lower part of the stem : blades narrow, equilateral, not oblique at the base, entire : stipules 

 gland-like, often obsolete. Involucres delicate, short-peduncled in the upper forks. 

 Glands 5, broader than long, subtended by petal-like appendages. Capsules long-pedi- 

 celled, 3-lobed. Seeds terete, usually narrowed upward, more or less papillose, the 

 caruncle sometimes wanting. SPURGE. 



1. Zygophyilldium hexagonum (Nutt. ) Small. Yellowish green, glabrous or spar- 

 ingly pubescent. Stems slender, 1-5 dm. tall, branched, the branches ascending, often almost 

 filiform : leaves mainly opposite ; blades linear, oblong or lanceolate, very short-petioled, 

 obtuse or acute, equilateral ; stipules obsolete or very narrow : involucres solitary in the 

 axils, often clustered, 2-3 mm. long, ciliate, pubescent, short-peduncled, with 5 glands ; 

 appendages triangular-ovate whitish or green : capsules glabrous, 4 mm. in diameter : seeds 

 ovoid or oblong-ovoid, 3 mm. long, terete, papillose. [Euphorbia hexagona Nutt.] 



On prairies, Iowa to Montana, Texas and Colorado. Spring to fall. 



25. TRICHEROSTIGMA Kl. & Garcke. 



Shrubs, with erect or procumbent stems and more or less succulent tissues. Leaves 

 scattered, few, usually fugacious : blades small, becoming firm. Stipules none. Invo- 

 lucres solitary, and subtended by fleshy bracts near the ends of the branches, or in axillary 

 cymes, hemispheric, pubescent within ; lobes toothed or fimbriate. Glands 5, subtended 

 by entire petal-like appendages. Capsule 3-lobed, exserted. Seeds 4-sided, someAvhat 

 wrinkled. 



