VERBENACEAE 1011 
20. Verbena ambrosifólia Rydb. Resembling V. bipinnatifida but larger. Stems 
and foliage less hirsute : leaf-blades less deeply and less finely divided, the segments typi- 
cally lanceolate: calyx becoming 8-9 mm. long; lobes setaceous-tipped, surpassing the 
bracts: corolla limb 6-8 mm. wide: nutlets 2.5 mm. long, coarsely wrinkled all over. 
In dry or stony soil, South Dakota and Colorado to Texas, Arizona and Mexico. Spring and 
summer, 
21. Verbena Drummóndii (Lindl.) Baxt. Perennial, but often flowering early. 
Stems often branched at the base, the branches 2-4 dm. long, hirsute : leaf-blades 2-5 cm. 
long, pinnatifid or bipinnatifid, the segments typically narrow : calyx becoming 9-10 mm. 
long, surpassing the bract at maturity : corolla limb fully 11 mm. wide: nutlets over 3 mm. 
long, wrinkled from below the middle to the apex. 
On prairies, or in sandy bottoms or woods, Virginia to Kansas, Texas and New Mexico. Spring 
and summer. 
22. Verbena Lambértii Sims. Perennial. Stem commonly branched at the base, 
the branches hirsute : leaf-blades 3-9 cm. long, typically of a lanceolate type, incised or in- 
cised-lobed, acute or acuminate at the apex, more or less cuneately narrowed at the base : 
calyx becoming 11-13 mm. long, surpassing the bract : corolla-limb 11-13 mm. wide : nut- 
lets about 3 mm. long, shallowly wrinkled throughout. 
Insandy or dry soil, Tennessee to Arkansas, South Carolina, Florida and Texas. Spring and 
summer, 
23. Verbena Canadensis ( L.) Britton. Perennial, stouter than the two preceding 
species. Stem or branches 3-6 dm. long, minutely pubescent or puberulent : leaf-blades 
3-8 cm. long, typically of an ovate type, incised or incised-lobed, rather rounded at the 
apex, cordate or broadly truncate at the base: calyx becoming 12-14 mm. long, mainly 
surpassing the bract : corolla-limb 12-15 mm. wide: nutlets 3.5 mm. long, wrinkled all over. 
On prairies, Illinois to Florida and Texas. Spring to fall. 
2. HELLERÁNTHUS Small. 
Annual pubescent herbs, more or less diffusely branched from the base. Leaves oppo- 
site: blades pinnatifid or parted. Flowers in terminal compact spikes, each subtended by 
a narrow bract. Calyx tubular, 5-lobed. Corolla white or pink: tube terete: limb 5- 
lobed. Stamens 4, didynamous: anthers unappendaged. Ovary 4-celled, surmounted by 
a hemispheric stylopodium. Stigma 2-lobed, one lobe stigmatic. Ovules solitary in each 
cavity. Fruit an aggregate of 4 tardily separating nutlets, the group surmounted by a 
pyramidal stylopodium, the whole enclosed in the calyx. f 
1. Helleranthus quadrangulatus (Heller) Small. Foliage hirsute. Stems branched 
at the base ; branches spreading or prostrate, 1-3 dm. long, forking: leaves numerous ; 
blades 1-2.5 cm. long, broadly ovate, incised-pinnatifid, or some 3-parted, the lobes incised 
or cleft, surfaces strigose-hirsute : spikes dense, 1-3 cm. long: bracts narrowly lanceolate, 
shorter than the calyx : calyx bristly, becoming 5 mm. long ; lobes acute : corolla white 
to pink ; tube surpassing the calyx ; limb 2.5-3 mm. broad, the lobes notched : fruit in- 
cluded, constricted at the middle, surmounted by a pyramidal stylopodium whose angles 
alternate with lobes. [ Verbena quadrangulata Heller. 
In dry soil, Texas. Summer. 
3. PHYLA Lour. 
Perennial caulescent procumbent or creeping herbs. Leaves opposite: blades flat, 
toothed or lobed. Flowers perfect, in congested peduncled axillary spikes, each subtended 
by a conspicuous persistent bract. Calyx membranous: tube flattened and 2-keeled, the 2 
lateral lobes conduplicate. Corolla 2-lipped: tube incurved, terete: limb oblique, the 
segments 4, often retuse or eroded. Stamens 4, didynamous, included : filaments short : 
anthers with unappendaged connectives. Ovary 2-celled. Stigma oblique or recurved. 
Ovules solitary in each cavity. Fruit dry, with a crustaceous or corky coat, tardily sepa- 
rating into 2 nutlets. The plants flower from spring to fall. 
Leaf-blades with 1-4 pairs of salient remote teeth near the apex. : UE 
Peduncles shorter than the subtending bracts or but little longer: fruit oval. 1. P. cuneifolia. 
Peduncles much longer than the subtending bracts : fruit obovoid. 2. P. incisa. 
f-blades with several pairs of low approximate teeth. : 
Leaf-blades mostly broadest above the middle, toothed from above the middle to : 
the apex : calyx-lobes shorter than the tube: fruit pubescent at the apex. 3. P. nodíftora. 
Leaf-blades mostly broadest below the middle, toothed from below the middle to 
the apex : calyx-lobes longer than the tube : fruit glabrous. 4. P. lanceolata. 
1. Phyla cuneifdlia ( Torr.) Greene. Foliage strigillose-canescent. Stems branched 
at the base; branches procumbent, rarely, if ever, creeping, 2-10 dm. long, often branch- 
