GENUS 12. 



SPURGE FAMILY. 



4 6 3 



$1$ Leaves serrate or dentate ; plants prostrate or spreading. 

 Herbage glabrous. 



Seeds faintly transversely ridged and pitted. 



Seeds brown, about l /i" long; leaves broad. 8. C. serpyllifolia. 



Seeds gray, about J4" long; leaves narrow. 9. C.albicaulis. 



Seeds strongly transversely ridged, not pitted. 10. C. glyptosperma. 



Herbage pubescent, or puberulent. 

 Capsules pubescent. 



Seeds narrow, fully y 2 " long, fully twice as long as wide, the faces pitted, n. C. stictospora. 

 Seeds broad, less than l / 2 " long, less than twice as long as wide, the faces wrinkled. 



Leaves broad; involucre deeply split on one side; seeds blunt-angled. 12. C. humislrata. 

 Leaves narrow ; involucre not deeply split; seeds sharp-angled. 13. C. maculata. 



Capsules glabrous. 14- C.Rafincsqui. 



Leaves serrate or dentate; plants erect or ascending. 15. C. Preslii. 



i. Chamaesyce polygonifolia (L.) Small. Seaside or Knotweed Spurge. 



Fig. 2732. 



Euphorbia polygonifolia L. Sp. PI. 455. 1753. 



Chamaesyce polygonifolia Small, Fl. SE. U. S. 708. 

 1903. 



Annual, pale green, glabrous, stem branched 

 from the base, the branches radiately spreading, 

 prostrate, forked, wiry, 3'-8' long. Leaves oppo- 

 site, oblong, linear-oblong or linear-lanceolate, 

 3"-io" long, fleshy, obtuse, often mucronulate, 

 entire, obtuse or subcordate and somewhat oblique 

 at the base, short -petioled ; stipules an inconspic- 

 uous fringe of short bristles ; involucres usually 

 solitary in the axils, turbinate-campanulate, less 

 than i" long, with 4 columnar nearly naked 

 glands shorter than the lobes ; peduncles twice as 

 long as the involucres ; capsule globose-ovoid, 

 iJ"-2" long, nodding, minutely wrinkled; seeds 

 ovoid, \\" long, somewhat flattened, ash-colored, 

 very minutely pitted and spotted. 



In sand along the Atlantic coast, Nova Scotia to 

 Florida, and on the shores of the Great Lakes. Shore-spurge. July-Sept 



2. Chamaesyce Geyeri (Engelm. & Gray) 

 Small. Geyer's Spurge. Fig. 2733. 



Euphorbia Geyeri Engelm. & Gray, Bost. Journ. Nat. 



Hist. 5 : 260. 1847. 

 C. Geyeri Small, Fl. SE. U. S. 709. 1903. 



Annual, olive-green, glabrous. Stem branched from 

 the base, the prostrate branches radiately spreading, 

 wiry, 2'-i5' long; leaves oblong or ovate, 2"-6" long, 

 obtuse, usually mucronulate, entire or nearly so, 

 oblique, obtuse or subcordate at the base, short- 

 petioled ; stipules a fringe of short setae ; involucres 

 usually solitary in the axils, campanulate, about $" 

 high, with 4 wineglass-shaped glands shorter than 

 the lobes, each subtended by an inconspicuous white 

 or red entire or lobed appendage ; peduncles as long 

 as the involucres, or longer; capsule globose-reni- 

 form, about i" long, nodding; seeds narrowly ovoid, 

 i" long, ash-colored, yearly terete. 



In sandy soil, Illinois to Minnesota, South Dakota and 

 Kansas. July-Sept. 



