708 



EUPHORBIACEAE 



** Stems much branched at the base : glands with toothed appendages : 



capsules over 1.5 mm. high. 

 Leaf-blades barely twice as long as broad : appendages of the 



glands narrow crenulate borders. 17. C, lata. 



Leaf-blades several times longer than broad : appendages of the 



glands nearly as long as broad, dentate or flmbriate. 18. C. angutia. 



b. Annuals. 



Foliage glabrous. 



Leaf-blades at least twice as long as broad. 



Capsules less than 1.5 mm. long 19. C. revoluta. 



Capsules over 1.5 mm. long. 



Glands of the involucre with inconspicuous appendages. 20. C. polyclada. 



Glands of the involucre with conspicuous appendages. 



Appendages mostly longer than broad : seeds 4-angled. 21. C. Nuttattii. 



Appendages mostly broader than long : nearly terete. 22. C. petaloidea. 



Leaf-blades about as long as broad. 



Leaf-blades involute, veinless above, apiculate. 23. C. buxtfolia. 



Leaf-blades revolute, manifestly veined above, rounded at the apex. 24. C. Porteriana. 

 Foliage pubescent. 25. C. vittifcra. 



B. Leaf-blades manifestly toothed, but sometimes only at the apex. 

 Capsules glabrous. 



Leaf -blades of a triangular tyx>e or orbicular to oval. 



Stems simple or sometimes branched at the base : leaf-blades mostly of a 



triangular type. 26. C. Stanfleldii. 



Stems copiously branched at the base : leaf-blades not triangular. 6. C. Chiogenes. 



Leaf-blades of an oblong, oblong-lanceolate or cuneate type. 

 Stems or branches prostrate. 



Seeds faintly if at all transversely wrinkled. 



Involucres less than 1 mm. high : capsules 1.5 mm. broad. 27. C. Blodgeltii. 



Involucres over 1 mm. high : capsules 2 mm. broad. 28. C. serpyllifotia. 



Seeds strongly transversely wrinkled. 29. C. glyptosperma. 



Stems or branches erect or ascending. 



Seeds brown or nearly black under a grayish coat : ultimate branches 



slender. 30. C. nutans. 



Seeds light gray : ultimate branches filiform. 31. C. Brasilientis. 



Capsules manifestly pubescent. 



Stems or branches erect or ascending. 



Stems or branches prostrate. 



Involucres axillary, sometimes approximate on lateral branchlets. 

 Involucres deeply split on one side. 



Foliage pale green : capsules over 1.5 mm. high : seeds fully 1 mm. 



long. 

 Foliage bluish green : capsules less than 1.5 mm. high : seeds less 



than 1 mm. long. 

 Involucres not split on one side. 



Capsules pubescent along the angles. 



Capsules pubescent all over, but mainly so below the middle. 

 Glands of the involucres with inconspicuous appendages. 

 Leaf-blades and involucres glabrous or sparingly pubescent. 

 Capsules with long spreading hairs along the angles : seeds 

 fully 1 mm. long, with strongly wrinkled faces. 



seeds 



32. C. Tracyi. 



33. C. humutrata. 



34. C. pergemena. 



35. C. prostrata. 



36. C. malaca. 



faces. 37. C. maculata. 



Capsules with short-appressed hairs along the angles : 

 less than 1 mm. long, with obscurely wrinkled : 

 Leaf-blades and involucres copiously pubescent, usually hirsute. 

 Glands of the involucre with red or magenta appendages, 

 2 of them at least large and somewhat petal-like : cap- 

 sules 1.5 mm. long : seeds over 1 mm. long. 38. C. conferta. 

 Glands of the involucre with pale, minute or obsolete ap- 

 pendages : capsules 1 mm. long : seeds much less than 

 1 mm. long. 39. C. stictospora. 

 Glands of the involucres with conspicuous petal-like appendages. 40. C. adaioptera. 

 Involucres in peduncled glomerules. 41. C. pilulifera. 



1. Chamae&yce polygonifolia (L. ) Small. Annual, pale green, glabrous. Stems 

 branched at the base, the branches radially spreading, prostrate, 1-2.5 dm. long, forked : 

 leaf-blades narrowly oblong to linear-lanceolate, 6-20 mm. long, fleshy, acute or apiculate, 

 entire : involucres turbinate-campanulate, less than 2 mm. long : glands 4, columnar, nearly 

 naked, shorter than the involucre-lobes ; appendages obsolete : capsules globose-ovoid, 3-4 

 mm. long, wrinkled in age : seeds oblong-ovoid, pale gray, minutely pitted. [Euphorbia 

 polygonifolia L. ] 



In sand, along or near the coast, New Hampshire to Florida, and along the Great Lakes. Summer 

 and fall. 



2. Chamaesyce Ingallsii Small. Annual, pale green, glabrous. Stems branched at 

 the base, the branches prostrate, dichotomous, 1-5 dm. long : leaf-blades oblong to ovate- 

 oblong, 8-16 mm. long, fleshy, entire ; petioles 1-3 mm. long : bracts similar to the leaves 

 but smaller : involucres campanulate, about 1 mm. high, as long as the peduncles : glands 

 about 0.3 mm. broad ; appendages obsolete : capsules ovoid-globose, 2.5 mm. long, 

 minutely wrinkled in age : seeds ovoid or globose-ovoid, less than 2 mm. long, white, spar- 

 ingly pitted. 



In sandy soil, Florida to Louisiana and Texas. Summer. 



