716 EUPHORBIACEAE 
b. Involucres 6-10 mm. across the appendages. 9. T. zinniiflora. 
B. Inflorescence aggregated into terminal cymes or cymose clusters. 
Leaf-blades manifestly petioled, the petioles over 2 mm. long. 10. T. apocynifolia. 
Leaf bindes sessile or nearly so, the petioles, if present, less than 1 mm. 
ong. 
Involucres 3.5 mm. across the appendages or narrower. 11. T. discoidalis. 
Involucres 4-8 mm. across the appendages. 
Appendages about as long as the involucre. 12. T. olivacea. 
Appendages much longer than the involucre. : 
Appendages longer than wide: leaf-blades relatively narrow. 13. T. corollata. 
Appendages as wide as long or wider: leaf-blades relatively 
broad. 14. T. paniculata. 
1. Tithymalopsis polyphylla (Engelm.) Small. Perennial, glabrous. Stems tufted 
or branched at the base, the branches erect or spreading, 0.5-2.5 dm. long, simple or more 
or less branched : leaves numerous, approximate, linear or linear-spatulate, 5-15 mm. long, 
straight or slightly curved, sessile: bracts oblong or linear-oblong : involucres turbinate- 
campanulate, about 1.5 mm. high, abruptly contracted at the base, shorter than the pedun- 
cles at maturity: glands 0.5-0.6 mm. broad ; appendages white or pinkish, reniform or 
mere undulate or crenate borders: capsules globular, 4-4.5 mm. in diameter : seeds oval, 
2.5 mm. long, smooth, white. [Euphorbia polyphylla Engelm. ] 
In sand, southern peninsular Florida. 
2. Tithymalopsis Ipecacuánhae (L.) Small. Perennial by a subterranean stem and 
root, usually glabrous. Branches several or many, slender, spreading or ascending, 1-3 dm. 
long, forking : leaves mostly opposite, green or red ; blades wonderfully variable in outline, 
from linear to orbicular, 1-7 cm. long, entire, the upper sometimes whorled, the lower 
sometimes alternate, short-petioled ; stipules triangular: involucres axillary, mostly hem- 
ispheric, about 2 mm. long, dleddesspatandled- bearing 5 transversely elliptic or nee 
green, sessile, narrowly appendaged glands: capsules 3 mm. in diameter, nodding: se 
light gray, oblong-ovoid, about 2.5 mm. long, pitted, obscurely 4-sided. i 
In dry sandy soil, Connecticut to Florida, mostly near the coast. Also in southern Indiana. 
Spring to fall. 
3. Tithymalopsis grácilis ( Ell. ) Small. Perennial, glabrous. Branches wiry, tufted, 
1-3 dm. long, trichotomous or dichotomous : leaves mainly opposite ; blades suborbicular 
to ovate or linear, or rarely broader than long, 1-5 cm. long, obtuse or retuse, or in the 
case of narrow ones acute, all entire, sessile or nearly so ; stipules triangular : peduncles as 
long as the accompanying leaves or longer: involucres campanulate or turbinate-campan- 
ulate, 2 mm. high : glands transversely oblong, less than 1 mm. broad, undulate and nar- 
rowly appendaged : capsules exserted, drooping, 2.5 mm. in diameter. 
In sand, South Carolina to Georgia and Florida. Spring to fall. 
4. Tithymalopsis erlogonoides Small. Perennial, deep green, glabrous. Branches 
several or many together, 1-3 dm. long, diffusely branched into a rounded head 1-3 dm. in 
diameter, the branches very slender, zigzag, the ultimate divisions nearly filiform : leaves 
opposite above, the larger ones often reflexed ; blades linear or linear-spatulate, 0.5-1.5 mm. 
long, obtuse or acutish, entire, barely petioled: peduncles filiform, 3-8 mm. long at 
maturity: involucres campanulate, about 1 mm. high, erect or ascending: glands reni- 
form, about 0.5 mm. broad ; appendages somewhat reniform, white or pink, about 1 mm. 
2 rea than the gland, some rounded, others emarginate. [Euphorbia eriog 
mall. 
In loose sand, eastern Georgia and Florida. Spring and summer. 
5. Tithymalopsis mercurialina (Michx.) Small. Perennial, bright green, nearly 
glabrous. Stems erect or decumbent, often several together, glabrous except à few scatte: ^ 
hairs about the nodes, forking above: leaves reduced to scales at the base of the stem: 
bracts foliaceous, opposite; blades oval, elliptic or oblong-ovate, 2-5 cm. long, entire 
somewhat undulate, obtuse, glabrous, except the ciliate margin, rather abruptly narrow! 
at the base, short-petioled : peduncles nearly filiform, 1-5 em. long: involucres campanu- 
late, 2 mm, high, erect or nearly so: glands transversely oblong, about 1 mm. b he 
appendages white, undulate, narrower than the gland: capsules exserted beyond the 
involucre. [Euphorbia mercurialina Michx. ] 
On hillsides and sandy soil, Tennessee to Alabama and Florida. Spring and summer. 
_ 6. Tithymalopsis Curtisii ( Engelm.) Small. Perennial, glabrous. Stems slender, 
solitary or several together, erect or ascending, 1-4 dm. tall, more or less branched : leaves 
scattered except the whorl subtending the umbel 3-5-rayed ; blades linear, 1.5-4 es 
long, usually acute: involucres campanulate, about 1 mm. high, much shorter t " 
the nearly filiform peduncles: glands green, transversely oblong, about 0.5 mm. b sens 
appendages white, petal-like, much larger than the gland, undulate : capsules subglobose, 
