Genus i6. 



SPURGE FAMILY. 



475 



II. Tithymalus Peplus (L. ) Hill. Petty Spurge. 

 Fig. 2763. 



Euphorbia Peplus L. Sp. PI. 456. 1753. 

 Tithymalus Peplus Hill, Hort. Kew. 172/3. 1768. 



Annual, glabrous. Stem rather slender, erect or nearly 

 so, 4'-i2' high, simple or branched, topped by a 3-5- 

 rayed umbel ; stem-leaves scattered, oblong or obovate, 

 4'-ii' long, obtuse or retuse, entire, crisped, narrowed 

 into a slender petiole; those at the base of the umbel 

 whorled ; bracts opposite, ovate or triangular-ovate, 

 apiculate, sessile ; involucres campanulate, almost ses- 

 sile, less than i" long, bearing 4 crescent-shaped unap- 

 pendaged glands prolonged into slender horns; capsule 

 globose-ovoid, i"-i4" in diameter, slightly nodding, 

 smooth, the lobes 2-keeled ; seeds oblong or oblong- 

 ovoid, whitish, nearly terete, marked with 1-4 series 

 of pits. 



In waste places, New Brunswick to western New York, 

 Wisconsin, Iowa, New Jersey. Pennsylvania and West Vir- 

 ginia. Bermuda, Jamaica. Adventive from Europe. Devil's- 

 milk. Seven sisters. Wartweed. June-Sept. 



12. Tithymalus commutatus (Engelm.) Kl. 



Fig. 2764. 



Tinted Spurge. 



rugose-pitted seeds, has been found in western Virginia. 



13. Tithymalus robustus (Engelm.) Small. 

 Rocky Mountain Spurge. Fig. 2765. 



Euphorbia commutata Engelm. in A. Gray, Man. Ed. 2, 



389. 1856. 

 Tithymalus commutatus Kl. & Garcke, Abh. Akad. Ber. 



1859: 82. 

 Euphorbia ohiotica Steud. & Hochst. ; Boiss. in DC. 



Prodr. 15: Part 2, 142. 1862. 



Biennial, yellowish green, often tinged with red, 

 glabrous. Stem slender, usually decumbent at the 

 base, 4'-i5' long, branched, topped by a 3-rayed 

 umbel ; branches forked or umbellately branched ; 

 leaves, except the whorl at the base of the umbel, 

 scattered, spatulate to ovate, i'-i4' long, obtuse or 

 mucronulate, entire, flat, narrowed into a slender 

 petiole; bracts opposite, ovate-reniform ; involucres 

 campanulate, iV long, sessile, bearings or 4 crescent- 

 shaped unappendaged glands prolonged into slender 

 horns; capsule globose-ovoid, li" in diameter, gla- 

 brous, the lobes rounded ; seeds oblong, terete, 

 irregularly pitted. 



On hillsides, chiefly along streams, Ontario to Minne- 

 sota, Pennsylvania, Florida and Missouri. March-July. 



Tithymalus falcatus (L.) Kl. & Garcke, a native of 

 Europe, with spatulate leaves, subulate-tipped bracts and 



robusta Engelm. Bot. Mex. Bound. 

 111. Fl. 2: 381. 



Euphorbia montana 



Surv. 192. 1859. 

 E, robusta Small, in Britt. & Brown, 



1897. 



Perennial by a perpendicular rootstock, glabrous, 

 glaucous. Stems slender, clustered, erect or assur- 

 gent,4'-i4' tall, slightly angled, scaly below, branched, 

 topped by a 3-S-rayed umbel ; leaves, except the 

 whorl subtending the umbel, scattered, ovate or 

 oblong-ovate, s"-8" long, thick, obtuse or apiculate, 

 entire, sessile; bracts opposite, triangular-ovate or 

 subreniform, involucres campanulate, li" long, ses- 

 sile, bearing 4 somewhat crescent-shaped unappend- 

 aged buff crenulate glands ; capsule globose-ovoid, 

 2" long, horizontal, its lobes rounded ; seeds oblong 

 or obovoid-oblong, terete, li" long, gray, minutely 

 pitted. 



Hills and plains. South Dakota to Montana, Wyoming, 

 Nebraska, Arkansas and Arizona. May-Oct. 



