EUPHORBIACEAE 715 
1. Tricherostigma antisyphilitica (Zucc.) Kl. & Garcke. Shrubby, glabrous. 
Stems procumbent ; branches erect or ascending, 2-8 dm. tall, stout, simple or nearly so, 
early leafless : leaves few, alternate ; blades linear, 10-18 mm. long, rigid, acute, recurved : 
bracts scale-like, leathery, triangular: involucres sessile, or nearly so, constricted at the 
base, 2-3 mm. high: glands transversely oblong, barely 1 mm. broad ; appendages white, 
longer than the glands, undulate, somewhat cucullate : capsules globose-ovoid, 3-3.5 mm. 
long, glabrous ; lobes rounded : seeds 2-2.5 mm. long, eA SEY white, irregularly wrinkled. 
On gravelly or limestone hillsides along the Rio Grande, Texas and Mexico. 
26. DICHROPHYLLUM KI. & Garcke. 
Annual caulescent herbs, with the erect stems often topped by a several-rayed umbel. 
Leaves scattered below the umbel, thence opposite or whorled : blades often petal-like and 
very showy, entire: stipules at the base of the petioles or leaf-blades, fugacious. Invo- 
lucres campanulate, in rather dense cymes, pubescent without and within : lobes fimbriate. 
Glands 5, peltate, somewhat concave, with white or pink petal-like appendages. Capsule 
exserted, large, pubescent, the lobes rounded. Seeds narrowed upward, reticulated, with 
caruncles. SPURGE. 
Bracts of a linear type, reddish margined : involucral glands with reddish appendages. 
1. D. bicolor. 
Bracts of an oblong type, white margined : involucral glands with white appendages. 2. D. marginatum. 
1. Dichrophyllum bicolor (Engelm. & Gray) Kl. & Garcke. Stem 3-15 dm. tall, 
usually topped by a 3-rayed simple or compound umbel : leaves scattered ; blades oblong 
to oblong-lanceolate or the lower ones slightly broadest above the middle, all sessile, apic- 
ulate; bracts linear or linear-spatulate, about as long as the leaves or longer: involucres 
campanulate, 3.5-4 mm. high, hairy, longer than the peduncles: glands rather reniform, 
1.5 mm. broad ; appendages white, reniform or fan-shaped, 3-4 mm. long, crenulate : cap- 
sules woolly, becoming about 1 cm. broad, much depressed, 3-lobed : seeds ovoid, 5-6 mm. 
long. [Euphorbia bicolor Engelm. & Gray. ] 
On rich plains, Arkansas and the Indian Territory to Louisiana and Texas. Spring to fall. 
2. Dichrophyllum marginàtum (Pursh ) Kl. & Garcke. Stem 3-9 dm. tall, somewhat 
channeled, usually pilose, topped by a mostly 3-rayed umbel: leaves scattered ; blades 
ovate to obovate, 2-9 cm. long, entire, sessile: rays of the umbel forked: bracts large, 
white-margined : involucres campanulate, often clustered, 4 mm. long, usually pubescent, 
bearing 5 glands subtended by white reniform appendages: capsules depressed-globose, 6 
mm. in diameter, usually pubescent, the lobes rounded : seeds ovoid-globose, terete, about 
4 mm. long, dark ash-colored, reticulate-tuberculate. [Euphorbia marginata Pursh. ] 
In dry soil, Minnesota to Colorado and Texas. Introduced into waste places in the Central and 
Atlantic States. Spring to fall. : 
27. TITHYMALOPSIS Kl. & Garcke. 
Perennial herbs, with tough rootstocks and glabrous or pubescent foliage. Stems soli- 
tary or tufted, topped by several-rayed umbels. Leaves alternate or scattered below the 
umbels, thence opposite or whorled : blades entire, more or less leathery, inclined to be 
revolute. Involucres sessile or peduncled, few and remote, or in rather close clusters and 
numerous: lobes toothed or fimbriate. Glands sessile or stalked, with white pink or 
rose petal-like appendages. Capsule exserted, sometimes conspicuously so, often broader 
than high: lobes rounded. Seeds narrowed upward, more or less conspicuously punctate, 
M caruncles. SPURGE. 
aves exceedingly numerous, approximate or imbricated. 1. T. polyphylia. 
Leaves relatively Ra never finteleated. r 
Mena normally wadergroubd ; branches of the inflorescence tufted ; all leaves 
8 opposite. 
Glands of the involucre with inconspicuous m n-like appendages. 
ranches spreading or prostrate: leaf-blades fleshy. 2. T. 
Branches erect or ascending : leaf-blades thin. 3. T. ; 
Glands of the involucre with conspicuous white appendages, 4. T. eriogonoides. 
Stems erect, topped by the umbel-like inflorescence, their leaves alternate. 
Stem-leaves reduced to scales: het: 
Stem-leaves with normally expanded blades. 
A. Inflorescence of scattered long-peduncled involucres. 
a. Involucres 2-4 mm. across the appendages. 
Stem-leaves with linear blades, fugacious. 6. T. Curtisii. 
Stem-leaves with oblong or lanceolate blades, persistent. 
Appendages about as broad as the glands or narrower. 7. T. ezserta. 
Appendages mainly much longer than the glands. 8. T. Joorii. 
