718 EUPHORBIACEAE 
umbel whorled : bracts ovate to linear, green: involucres mostly terminal, less than 2 mm. 
long, bearing 4 or 5 yellowish green oblong glands subtended by white petal-like cuneate or 
orbicular-cuneate appendages: capsules erect, subglobose, 3-4 mm. in diameter: seeds 
smooth, sparingly pitted. [Euphorbia corollata L.] 
In dry soil, Ontario to Minnesota, Massachusetts, Kansas, Florida and Texas. Spring to fall. 
14. Tithymalopsis paniculata ( Ell.) Small. Perennial, deep green. Stems often 
solitary, erect, 3-9 dm. tall, simple below, pubescent, especially about the nodes, the umbel 
3-5-rayed, the rays more or less ey forked : leaves alternate below the whorl, sub- 
tending the umbel ; blades oblong to oval, 2-6 cm. long, obtuse, glabrous or hairy along 
the midrib and pale green beneath, somewhat revolute, abruptly narrowed or truncate at 
the base, slicrtspettoled or nearly sessile : involucres rather crowded in loose terminal clus- 
ters, short-peduncled, campanulate, terete, 1.5 mm. high: glands transversely oblong, 
about 1 mm. broad ; appendages white, suborbicular or somewhat 4-sided, fully 1 mm. long, 
entire : capsules about 3 mm. long, glabrous. [Euphorbia paniculata Ell.] 
In sandy soil, North Carolina to Georgia. Summer. 
28. TITHYMALUS Adans. 
Annual or perennial herbs or shrubby plants, with simple or branched stems, which are 
topped by several-rayed umbel-like cymes. Leaves below the umbel usually scattered or 
alternate, without stipules: blades often broadened upward. Bracts of the umbel quite 
different from the stem-leaves: blades entire or toothed. Involucres sessile or peduncled, 
axillary, disposed in open or close cymes: lobes often toothed. Glands 4, transversely 
oblong, reniform or crescent-shaped by the horn-like appendages, the missing one repre- 
sented by a thin often ciliate lobe. Capsule exserted, smooth or tuberculate: lobes 
rounded, sharp or keeled. Seeds variously pitted, often with caruncles. SPURGE. 
Leaf-blades entire: glands of the involucre crescent-shaped, reniform or truncate. ; 
Leaves of the stem or main branches opposite. 1. T. Lathyris. 
Leaves alternate. 
Bracts or leaves of the rays opposite: rays diehotomous. 
Glands of the involucre without horn-like processes. 
Glands with erose-crumpled edges. 2. T. sphaerosperma. 
Glands entire or merely undulate. 
Bracts of the rays longer than broad. ; 
Stem-leaves linear to linear-lanceolate. 8. T. inundatus. 
Stem-leaves obovate to oblanceolate. 4. T. telephioides. 
Bracts of the rays fully as broad as long. 5. T. Darlingtonii. 
Glands of the involucre crescent-shaped by horn-like processes. a 
Seeds smooth. 6. T. Helleri. 
Seeds variously pitted. 
Surfaces of the seeds rather finely and irregularly pitted. m 
Bracts of the rays very inequilateral, longer than the internodes. 7. T. longicuris. 
Bracts of the rays equilateral, shorter the internodes. 
Stem-leaves with spatulate to ovate blades: bracts ovate-reni- 
form: seeds pitted. 8. T. commutatus. 
Stem-leaves with linear blades: bracts deltoid: seeds reticulated. 9. T. austrina. 
Surfaces of the seeds longitudinally grooved or with large pits in 
longitudinal rows. 
Capsules with prominently keeled lobes. 10. T. Peplus. 
Capsules with rounded lobes. ge 
s with 2 grooves on the inner face. 11. T. Peplidion. 
Seeds with several pits on the inner face. 12. T. tetraporus. 
Bracts or leaves of the rays alternate: rays trichotomous. 13. T. trichotomus. 
Leaf-blades serrulate. P 
Glands of the involucres furnished with 2 horn-like AME. 14. T. Roemerianus. 
Glands of the involucres transversely oblong, unappendaged. 
Capsules warty. 
Stem-leaves with cordate or truncate bases. 15. T. obtusatus. 
Stem-leaves with narrowed bases 
bae aen tects merely sessile: bracts of the umbel manifestly longer 
an A 16. T. Arkansanus. 
Upper stem-leaves with small basal lobes: bracts of the umbel about 3 x 
as broad as long or broader. 17. T. Missouriensis. 
Capsules smooth. 18. T. leiococcus. 
1. Tithymalus Lath L.) Hill. Annual or biennial, glabrous, glaucous. Stem 
usually erect, stout, ETETA tall, mostly simple below, ani bellatal branched above: 
leaves numerous, mostly opposite, the lower with linear reflexed blades, the upper with n 
olate or linear-lanceolate ‘ales 3.5-12 cm. long, these entire, sessile, subcordate at the 
base: bracts of the rays opposite, ovate or ovate-lanceolate, truncate or subcordate : ad 
volucres 5 mm. Jong, bearing 4 crescent-shaped unappendaged glands prolonged into ee 
horns : capsules subglobose, 10-12 mm. in diameter, the lobes rounded : seeds oblong-ovol@, 
5-6 mm. long, terete, usually wrinkled, dirty-brown. [Euphorbia Lathyris L.] 
In waste places, New Jersey to North Carolina and Texas. Also in California. Native of Europe. 
Spring and summer. 
