EUPHOKBIACEAE 717 



3 mm. high, glabrous, seated on the involucre : seeds subglobose, about 2 mm. long, 

 smooth. [Euphorbia Curtisii Engelm. ] 



In pine lands, North Carolina to Florida. Summer. 



7. Tithymalopsis exse~rta Small. Perennial, glabrous, branched at the base, the 

 branches closely or loosely tufted, 1-3 dm. long, forking above, reddish or purple : leaves 

 alternate below the umbel, thence opposite ; blades oblong or lanceolate, 2-6 cm. long, 

 obtuse or acutish, somewhat undulate, sessile or nearly so : peduncles filiform, 1-3.5 cm. long 

 at maturity : involucres campanulate, nearly 2 mm. high, white or whitish green, erect : 

 glands transversely oblong, less than 1 mm. broad ; appendages narrow undulate borders 

 or a mere line : capsules 4 mm. in diameter, well exserted beyond the involucres : seeds 

 3-3.5 mm. long. 



In pine lands, Florida. Summer. 



8. Tithymalopsis Joorii (Norton) Small. Perennial, glabrous or pubescent. Stems 

 1-1.5 dm. tall, sparingly branched at the base and above : leaves alternate, few ; blades 

 ovate to broadly oblong, 1-2 cm. long, obtuse, sometimes undulate, sessile : peduncles 10- 

 25 mm. high : involucres few, 2-2.5 mm. high : glands narrow ; appendages suborbicular 

 to cuneate, one or two of them often imperfect : capsules globular, somewhat depressed, 

 3-4 mm. broad : seeds globose-ovoid. [Euphorbia corollata var. Joorii Norton.] 



In dry soil, eastern Texas. Spring and summer. 



9. Tithymalopsis zinniiflora Small. Perennial, dark green. Stems usually solitary, 

 erect, 3-5 dm. tall, with a few ascending branches below the 3-rayed umbel, pubescent 

 with scattered hairs : leaves alternate except those subtending the umbel ; blades narrowly 

 linear-lanceolate, or nearly linear, 2-5 cm. long, mostly reflexed, acute or rather obtuse, 

 sparingly pubescent above, glabrate beneath, somewhat revolute, nearly sessile or with 

 somewhat hairy petioles less than 1 mm. long : peduncles slender, erect, 1-3.5 cm. long, 

 angled, especially above : involucres campanulate, 2 mm. high, angled : glands oblong- 

 reniform, fully 1 mm. broad ; appendages white or pink, suborbicular or 4-sided, 3 mm. 

 long, rounded or emarginate at the apex : capsules 4.5-5 mm. in diameter. [Euphorbia 

 zinniiflora Small.] 



In sandy soil, Georgia and Alabama. Spring. 



10. Tithymalopsis apocynifolia Small. Perennial, bright green. Stems solitary or 

 tufted, erect or ascending, 2-6 dm. tall, slender, pubescent or glabrate, zigzag, at least at 

 maturity, the umbel 2-3-rayed, the rays dichotomous, wire-like or filiform, ascending : 

 leaves alternate except the whorl or pair subtending the umbel ; blades thinnish, oblong to 

 oval, 2-7 cm. long, obtuse, slightly revolute, pale beneath, with glaucous midrib sometimes 

 pubescent on both sides ; petioles 3-6 mm. long, densely villous : bracts opposite, similar 

 to the leaves but smaller : peduncles filiform, glabrous : involucres campanulate, barely 1.5 

 mm. high, glabrous : glands transversely oblong, about 0.5 mm. broad ; appendages white, 

 orbicular-cuneate, 1.5-2 mm. long, rounded at the apex: capsules about 5 mm. in diam- 

 eter [Euphorbia apocynifolia Small.] 



In sandy soil, Georgia and Florida to Mississippi. Summer and fall. 



11. Tithymalopsis discoidalis (Chapm. ) Small. Perennial, sparingly pubescent or 

 glabrous. Stems erect or ascending, the umbel usually 3-rayed, the rays mostly forked, 

 slender : leaves scattered except those subtending the umbel ; blades linear, 2-6 cm. long, 

 obtuse, revolute, paler beneath, sessile : involucres campanulate, at least 1 mm. high, as 

 long as the peduncle or shorter : glands deep red, transversely oblong, 1 mm. broad ; ap- 

 pendages reniform, white : capsules subglobose, 3 mm. high, the angles rounded : seeds 

 ovoid, pale red. [Euphorbia discoidalis Chapm. ] 



In dry sand, Florida. Summer and fall. 



12. Tithymalopsis olivacea Small. Perennial, olive green, glabrous. Stems sol- 

 itary or several together, 2-7 dm. tall, simple or branched at the base, the branches erect 

 or ascending, forking above or topped by a 3-rayed umbel : leaves alternate below the 

 umbel ; blades leathery, oblong, obovate-oblong or cuneate, 1-3 cm. long, obtuse, or notched 

 at the apex and with a short mucro, sessile or short-petioled : involucres scattered along 

 the slender branchlets, campanulate, about 1.5 mm. high, angled: glands transversely ob- 

 long, about 0.5 mm. broad ; appendages white, 1-5 mm. long, orbicular cuneate, minutely 

 erose at the top : capsules 3.5-4 mm. in diameter. [Euphorbia olivacea Small.] 



In sandy soil, northern Mississippi. Summer. 



13. Tithymalopsis corollata (L. ) Small. Perennial by a long stout rootstock, bright 

 green, glabrous or somewhat pubescent. Stems erect, 2-9 dm. tall, often spotted, usually 

 simple, the umbel several-rayed : leaves opposite ; blades linear, oblong, or oblong-spatulate, 

 2-4 cm. long, entire, short-petioled or sessile, the lower scattered, those subtending the 



