387 
obtuse, with revolute margins; stipules triangular-lanceolate: involucre axillary or 
terminal, campanulate, hairy, with elongated lobes: pod hirsute: seed oblong-te- 
tragonal, transversely wrinkled,—From the Upper Rio Grande and the Pecos to Eagle 
Springs and Runnels. 
3. BE. angusta Engelm. Erect (2 to4dm, high), with several stems from a large 
black root and elongated branches: leaves lanceolate-linear (1 to 1.5m, long), acute, 
the margin subrevolute, at last glabrous; stipules subulate, minute, deciduous: in- 
volucres solitary in the upper axils, turbinate, the ovate lobes fimbriate: pod white: 
seed ovate-tetragonal, irregularly and transversely rugose, 1.6 mm, long.—From Tom 
Green County to San Diego and the Lower Rio Grande, , 
* * Kyect annuals, with short petioled leaves, eymose involucres, appendiculate glands, and 
transversely rugose 4-angled seeds. 
4. EB. pilulifera L. Pubescent: stems (1 to 1.5 dm. high) forking from the base: 
leaves oblong-ovate (10 to 16 mm, long), oblique, acute at each end, serrate: involu- 
eres minute, in dense terminal short-stalked clusters; glands with narrow or obso- 
lete appendages: pod acute-angled, hairy: seeds rugulose.—Extending from the 
Gulf States through Texas to New Mexico. 
5. E. hypericifolia L. Smooth throughout, 2 to 3 dm. high, with alternate 2- 
ranked branches: leaves (1.5 to 2.5 em. long) lanceolate-oblong, oblique and obtuse 
or acute at base, equally serrate on both margins; stipules retlexed: involucres in 
dense lateral long-pedunculate clusters: pods rather acutely angled, smooth: seeds 
reddish.—Extending from the Gulf States to southwestern Texas and Mexico. 
6. E. Preslii Guss. Smooth or with seattered hairs, ascending or erect, 3 to 6 din. 
high: leaves oblique at the obtuse or slightly cordate base, ovate-oblong or oblong- 
linear, sometimes faleate, serrate (1.5 to 3.5 cm, long), often with a red spot or red 
margins; stipules triangular: peduncles longer than the petioles, collected in a loose 
leafy terminal cyme: appendages entire, larger and white or smaller and sometimes 
red; pod glabrous, obtusely angled: seeds ovate, obtusely angled, wrinkled as well 
as tubereled, 1mm. long, blackish.—From Tom Green County throughout central 
and southern Texas. 
*** Tow spreading and mostly procumbent plants, with mostly minute and non-attenuate 
leaves, mostly solitarg involucres and 4 (often appendiculate) glands. 
+ Seeds smooth: leaves entire. 
++ Glabrous annuals. 
7. B. polygonifolia L. Prostrate spreading: leaves oblong-linear, obtuse, mucro- 
nate, slightly cordate or obtuse at base, &® to 16 mm, long; stipules setaceously 
divided: peduncles in the forks, as long as the petioles: lobes of the involucre longer 
than the minute non-appendaged glands: pods obtusely angled: seeds ovate, over 
2mm, long.—Dry sandy and rocky places along the Rio Grande from E] Paso to the 
Gulf and north to Gillespie County. 
8. B. petaloidea Engelm. Stems procumbent or ascending: leaves attenuate to 
the seareely oblique base, oblong-linear or linear, retuse or emarginate: involucre 
campanulate, lobes hairy beneath the glands within, the broadly campanulate ap- 
pendages conspicuous: peduneles longer than the petioles: seeds reddish, with 
rounded angles.—Valley of the Pecos and lower Rio Grande. 
9. EB. flagelliformis Engelm. Resembling /. petaloidea, but distinguished by 
the smaller involucre bearing very small and almost naked glands (often less than 4 
in number), more numerous stamens (often 25) with much smaller anthers, and the 
smaller more angular and more pointed grayish seeds. (EL. petaloidea, var, flagelliformis 
Eng.)—On the Rio Grande near El Paso and northward to southwestern Colorado. 
10. BE. zygophyloides Boiss. Stems erect-spreading (6 dm, high or more), with 
slender elongated dichotomous branches: leaves linear (12 to 14 mm, long), truncate 
