Genus i6. 



SPURGE FAMILY. 



475 



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

 Fig. 2703. 



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

 Tithymalus Peplus Hill, Hort. Kew. 172/3- i/^S- 



Annual, glabrous. Stem rather slender, erect or nearly 

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

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

 4-1 i' 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"-li" 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, .\dventive from Europe. Devil's- 

 milk. Seven sisters. Wartweed. June-Sept. 



12. Tithymalus commutatus (Engelm.) Kl. & Garcke. 



2764. 



Fig. 



Tinted Spurge. 



A. Gray, Man. Ed. 2, 



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



13. Tithymalus robustus (Engelm.) Small. 

 Rocky [Mountain Spurge. Fig. 2765. 



Euphorbia montana (3 robusta Engelm. Bot. Mex. Bound. 



Surv. IQ2. 1859. 

 E. robusta Small, in Britt. & Brown, 111. FI. 2: 381. 



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 3-5-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, 1 1" long, gray, minutely 

 pitted. 



Hills and plains. South Dakota to Montana, Wyoming, 

 Nebraska, Arkansas and Arizona. May-Oct. 



Euphorbia coinmutata Engelm. 



389. 1856. 

 Tilhvinalus 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'-l*' long, obtuse or 

 mucronulate, entire, flat, narrowed into a slender 

 petiole; bracts opposite, ovate-reniform ; involucres 

 campanulate, li" long, sessile, bearing 3 or 4 crescent- 

 shaped unappendaged glands prolonged into slender 

 horns; capsule globose-ovoid, i*" 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 



