592 FLORA. 



3. Euphorbia Nuttallii (Engelm.) Small. Prairie Spurge. (I. F. f. 2309.) 

 Bright green, glabrous. Stem slender, erect or ascending, 1-6 dm. high, the 

 branches wiry; leaves mostly linear and mucronulate or truncate at the apex, often 

 involute, obtuse or narrowed at the base, usually curved; involucres campanulate, 

 less than 2 mm. long, long-peduncled, bearing 4 saucer-shaped glands subtended 

 by white oblong or ovate appendages; seeds ovoid, 1.5 mm. long, gray, 4-angled. 

 Prairies, Mo. to Tex. and Mex. June-Sept. 



4. Euphorbia Geyeri Engelm. & Gray. Geyer's Spurge. (I. F. f. 2310.) 

 Olive-green, glabrous. Branches prostrate, radiately spreading, wiry, 5-40 cm. 

 long; leaves oblong or ovate, 4-12 mm. long, obtuse, usually mucronulate, entire 

 or nearly so, oblique, obtuse or subcordate at the base; involucres campanulate, 

 about 1 mm. high, with 4 wineglass shaped glands shorter than the lobes, and 

 inconspicuous white or red appendages; capsule globose-reniform, about 2 mm. 

 long; seeds narrowly ovoid, ash-colored, nearly terete. In sandy soil, Minn, to 

 111., S. Dak. and Kans. July-Sept. 



5. Euphorbia serpens H.B.K. Round-leaved Spreading Spurge. (I. F.f. 

 2311.) Pale green, glabrous, sometimes glaucescent. Branches slender or filiform, 

 prostrate, 5-30 cm. long; leaves orbicular, orbicular-ovate or oval, 2-6 mm. long, 

 obtuse or emarginate, entire, often slightly revolute, the base oblique, rounded or 

 subcordate; involucres solitary in the axils, nearly I mm. high, bearing 4 sessile 

 saucer-shaped glands shorter than the lobes, and minute irregular appendages; cap- 

 sule nodding, depressed-globose, 2 mm. in diameter; seeds oblong-ovoid, smooth, 

 obtusely 4-angled, light gray. 111. to Iowa and S. Dak., south to Mex. March-Oct. 



6. Euphorbia serpyllifolia Pers. Thyme-leaved Spurge. (I. F.f. 2312.) 

 Deep green, or becoming reddish, glabrous. Branches slender, prostrate, 1-3 dm. 

 long; leaves oblong to oval, 3-15 mm. long, obtuse or retuse, serrulate to below the 

 middle, the base oblique, mostly truncate or obtuse; involucres solitary in the 

 axils, sometimes clustered toward the ends of the branchlets, less than 2 mm. long, 

 bearing 4 disk-like glands and narrow lobed appendages; capsule 2 mm. broad; 

 seeds ovoid, 4-angled, the faces transversely wrinkled and pitted. In dry soil, Wis. 

 to Cal., south to Mex. May-Sept. 



7. Euphorbia albicaulis Rydb. White-stemmed Spurge. Pale green or 

 yellowish. Branches procumbent, 1-3 dm. long, glabrous, shining; leaves linear 

 or slightly broadened upward, I— 1.5 cm. long, nearly entire or toothed at the 

 apex; involucres turbinate, about 1 mm. high; appendages minute, rather broad, 

 white, truncate or crenulate; capsule about 2 mm. long, smooth, acute-angled; 

 seeds light brown, oblong, 1.3-1.5 mm. long, acutely 4-angled, shallowly trans- 

 versely wrinkled. In sandy soil, Neb. and Mont. June-Sept. 



8. Euphorbia glyptosperma Engelm. Ridge-seeded Spurge. (I. F. f. 

 2313.) Pale green, glabrous. Branches spreading or prostrate, 5-40 cm. long; 

 leaves oblong, linear-oblong or rarely ovate, 2-12 mm. long, more or less falcate, 

 obtuse at the apex, inequilateral, serrulate, very oblique and obtuse or subcordate 

 at the base; involucres solitary in the axils, campanulate, I mm. long, with 4 dark 

 ribs and 4 saucer-shaped glands, their appendages narrow; capsule depressed-glo- 

 bose, less than 2 mm. in diameter; seeds oblong, ash-colored, transversely wrinkled. 

 In sandy soil, Ont. to Br. Col., Conn., Tex. and Mex. June-Oct. 



9. Euphorbia hirsuta (Torr.) Wiegand. Hairy Spurge. (I. F. f. 2314a.) 

 Bright green, more or less hirsute. Branches prostrate or decumbent, 5-25 cm. long, 

 zigzag; leaves ovate-oblong, 8-16 mm. long, acutish, serrulate nearly to the oblique 

 base, pale beneath; involucres funnelform, I mm. high, glabrous, bearing 4 

 stalked saucer-shaped dark brown glands, and white appendages; capsule about 2 

 mm. in diameter, broader than long, glabrous, its angles obtuse; seed 4-angled, 

 black beneath a white coating, its faces slightly wrinkled. In sandy or gravelly 

 soil, Quebec and Ont. to Conn., N. Y. and Penn. June-Sept. 



10. Euphorbia maculata L. Milk Purslane* Spotted or Blotched 

 Spurge. (I. F. f. 2314.) Dark green, puberulent or pilose. Branches slender, 

 radiately prostrate, 5 40 cm. long, often dark red; leaves usually blotched, oblong 

 or ovate-oblong, 4 16 mm. long, obtuse, more or less serrate, the base oblique, sub- 

 cordate; involucres solitary in the axils, 2 mm. long, with 4 cup-shaped glands, the 

 appendages narrow, whin or red; capsule ovoid-globbse, about 2 mm. in diameter, 

 pubescent; seeds ovoid-oblong, obtusely angled, minutely pitted and transversely 



