396 AMARANTHACEAE 
oblong or elliptic, 1.5-6 cm. long, obtuse, commonly mucronate, entire, sessile or some- 
what petioled: spikes dull straw-colored, 6-12 mm. long, sessile, at maturity resembling 
the flower-clusters of Ephedra, leaving a conspicuous scar when detached : bracts ovate, 
keeled : calyx 3 longer than the bracts: sepals rigid, ovate, acute and slightly awn-tipped, 
usually 5-nerved, glabrous : staminodia longer than the filaments, cleft or lacerate at the tip. 
In sand, peninsular Florida and tropical America. 
4. Alternanthera philoxeroides (Mart.) Griseb. Plants glabrous or nearly so. 
Stems or their branches prostrate or decumbent, freely creeping, the ascending portion often 
1-5 dm. long, the upper internodes often a little hairy : leaf-blades somewhat fleshy, linear 
to linear-oblanceolate, 2-10 cm. long, usually acute or mucronulate, entire, narrowed to the 
sessile base: spikes subglobose or cylindric, long-peduncled, silvery white: peduncles 2-7 
cm. long, glabrous or pubescent in lines: sepals 5-6 mm. long, glabrous, unequal, 4-nerved, 
lanceolate, acute, firm : staminodia narrow, usually entire. 
In waste places, South Carolina to Florida and Louisiana. Also in tropical America. 
5. Alternanthera Moquínii Webb. Plants suggesting broad-leaved species of Allionia. 
Foliage glabrous or glabrate: stems erect or ascending, 3-8 dm. tall, sparingly forked: 
leaves about as long asthe internodes ; blades broadly ovate, 4-8 cm. long, acute or slightly 
acuminate, entire, abruptly narrowed or truncate at the base, short-petioled : spikes slender- 
peduncled, ovoid, less than 1 cm. long: peduncles shorter than the leaves : sepals 3-3.5 
mm. long, glabrous, mainly lanceolate, acute, surpassing the ovate, scarious-margined 
acuminate bracts : staminodia surpassing the anthers and the very short filaments, fringed 
at the apex: utricle included. 
In sand, Key West, Florida. Also in tropical America. 
6. Alternanthera Floridana (Chapm.)Small. Plants slender. Pubescence minute, 
appressed : stems erect, 6-14 dm. tall, forking, the internodes elongated : leaves much shorter 
than the internodes ; blades lanceolate to elliptic, 1.5-3 em. long, acute or acuminate, 
entire, short-petioled or nearly sessile: spikes ovoid, about 1 cm. long, silvery white: 
peduncles conspicuously elongated, many times longer than the leaves : sepals about 4 mm. 
long, minutely pubescent, lanceolate or one of them broader, all acute, surpassing the 
bracts: staminodia longer than the narrowly elongated filaments: utricle with a toothed 
crown. [ Telanthera Floridana Chapm.] 
In sand, peninsular Florida and the Keys. 
7. Alternanthera Brasiliàna (L.) Kuntze. Plants stoutish. Pubescence compara- 
tively long and coarse : stems erect, 0.5-2 m. tall, more or less forked, pubescent with as- 
cending or spreading hairs : leaves commonly as long as the rather short internodes ; blades 
lanceolate or oblong-lanceolate, 3-10 cm. long, acuminate, entire, cuneate or somewhat 
rounded at the base, short-petioled : spikes slender-peduncled, ovoid to cylindric, 1-2.5 
em. long: sepals 4-4.5 mm. long, lanceolate or oblong-lanceolate, acute, finely pubescent : 
anthers nearly sessile, or filaments very short: staminodia much surpassing the anthers: 
utricle with an entire crown. 
In sand, peninsular Florida and tropical America. 
9. CLADOTHRIX Nutt. 
Annual or perennial, diffusely branched herbs. Foliage pubescent with stellate hairs. 
Leaves mainly opposite: blades entire or merely undulate, short-petioled. Flowers per- 
fect, subtended by 3 bracts, solitary or clustered in the axils. Sepals 5, equal, pubescent, 
thin. Hypanthium small or obsolete. Stamens 5, hypogynous : filaments united at their 
bases: anthers l-celled. Ovary 1-celled, subglobose : style short: stigma capitate or 2- 
lobed. Ovule solitary. Utricle subglobose, indehiscent. 
Annual: stems or branches mostly prostrate or procumbent. 1. C. lanuginosa. 
Perennial: stems or branches erect or ascending. 2. C. suffruticosa. 
1. Cladothrix lanuginósa Nutt. Annual, lanuginose. Stems branched at the base, 
the branches procumbent or prostrate, 1-6 dm. long, forking, terete: leaves sometimes 1n 
3’s at the joints, 2 smaller than the third ; blades suborbicular, ovate or rhombic-ovate, 
obtuse or emarginate at the apex, entire, 0.5-2 cm. long, rather prominently nerved 
beneath, more or less abruptly contracted and often oblique at the base : flowers usually in 
pairs : bractlets obtuse, pubescent : sepals twice as long as the bractlets, narrower, obtuse, 
glabrous, l-nerved : utricle glabrous, included in the calyx. 
In dry soil, Kansas to Texas, Arizona and Mexico. Spring to fall. 
2. Cladothrix suffruticdsa ( Torr.) S. Wats. Perennial, lanuginose. Stems erect 
or ascending, several from a woody base, forking, 1-1.5 dm. long, the branches ascending : 
