302 
-forked, the forks again 2 to 3 (rarely 5)-forked: involucres long-peduncled, with 
showy white appendages (petal-like), the lobes minute and ineurved: pod slender- 
pedicelled, smooth: seeds thick (2 mm. long or more), ash-colored, slightly uneven.— 
Extending into Texas from the Atlantic States. 
37. B. Wrightii Torr. & Gray. Stems herbaceous from a somewhat ligneous base, 
much branehed (3 dm, or more high): leaves narrowly lanceolate-linear (2.5 to3 em. 
long): involucres solitary, pedunculate, mostly terminal, pubescent; glands trans- 
versely oblong, with large petaloid broadly obovate denticulate appendages: pod 
coriaceous, minutely papillose-pubescent: seeds subglobose, glabrous.—From the 
headwaters of the Colorado to the San Felipe and San Pedro. 
Pa 
§5. Skrubby: leaves sparse, entire; stipules none: involucres axillary: glands 5, with 
entire appendages.—TRICHEROSTIGMA, 
38. E. antisyphilitica Zuce. Stems ligneous, procumbent, with the Ephedra-like 
branches erect, subsimple, soon leatless: leaves linear, 16 mm, long, acute, recurved, 
rigid; the floral scale-like, leathery, triangular, blackish: involucres solitary in the 
axils, forming a loose terminal spike; glands transversely oblong, with a broader 
white cucullate subdentate appendage: pod glabrous, large, obtusely angled: seeds 
white, d-angled, irregularly wrinkled.—Gravelly and limestone hills of the Rio 
Grande. 
B. Glands of the involucre without petaloid appendages. 
§ 6. Involucres in terminal clusters, 4 or 5-lobed, with few cup-shaped glands: erect an- 
nuals, with variable leaves, the lower (sometimes the upper) alternate, and the stipules 
glandular.—POINSETTIA,. | 
39. BE. dentata Michx. Erect or ascending (3. dm. high): leaves ovate, lanceolate, 
or linear, petioled, coarsely toothed (2.5 to5 em. long), only the lowest alternate, 
the upper often paler at base: involucres almost sessile, with 5 oblong dentate 
lobes, and one or sometimes more short-stalked glands: seeds ovate, sligtly tuber- 
culate,— Valleys of the Pecos and the Rio Grande. Var. R1GIpA Engelm, is lower 
(1.5 dm. high), with rigid stems, and smaller coriaceous reticulate leaves with revo- 
lute margins.— Headwaters of the San Pedro. 
40, E. heterophylla L. Erect (3 to dm. high), glabrous: leaves alternate, peti- 
oled, ovate, fiddled-shaped and sinuate-toothed, or lanceolate or linear and entire, 
often only those of the branches linear, the upper usually with a red base: inyo- 
lucres about the length of the peduncle, with 5 ovate incised lobes, and a single or 
few and almost sessile glands: seeds nearly globular, tubercled.—Along the valleys 
of the Pecos and lower Rio Grande. Var. GRAMINIFOLIA Engel. has linear-lanceo- 
late often entire leaves more hairy beneath.—Crevices of rocks and dry beds of 
rivers, from El Paso to Uvalde and Georgetown. 
41. E. cuphosperma Boiss. Stems slender, strict, scarcely branched: leaves 
petioled, narrowly linear-lanceolate, acute, subentire, the lower alternate, the others 
opposite: involucres 3 to 5, corymbose, subsessile, campanulate, with ovate lobes; 
glands 4, long-stipitate, tubular: seeds subpyramidal, triangular, with a single 
sulcus, tuberculate. (4. dentata, var. cuphosperma Eng.)—Western Texas, near the 
Rio Grande. 
42. EB. barbellata ingelm, Glabrate: stem slender (3 dm. or more high), sub- 
simple: leaves subsessile (5 to 10 em. long), linear-lanceolate, remotely agd sharply 
dentate or ovate-3-lobed from a long (pilose-barbed) cuneate base, the middle lobe 
strongly elongated, acute; the floral ovate or elongated from a dilated rose-colored 
base: flowers in large glomerules: involucres large, subsessile, glabrous; glands 
single, sessile on the incised-dentate lobes.—From the Rio Grande, near Eagle Pass, 
to Uvalde. 
43. E. geniculata Ort. Stems dichotomously corymbose above: leaves (lower) 
alternate with acuminate base, petiolate, ovate or oblong, acute, entire or obsoletely 
