atoll research bulletin no. 392 the flora of - Smithsonian Institution ...

to 2.5 cm wide, simple, alternate, lanceolate to ovate, acute, or variably shaped, the
upper ones narrower, smaller and subsessile, the lower ones with surfaces minutely
puberulent, base decurrent, irregularly toothed, with winged petioles, 1 to 3 cm long;
flowerheads, 6 to 7 mm long, in loose terminal paniculate clusters on slender peduncles;
involucral bracts, 4 to 5 mm long, green with brownish tips, lanceolate, 4-ranked (4-
seriate), puberulent; ray-florets, absent; disc-florets, about 4 mm long, 20 to 25 in
number, tubular, violet or pinkish violet, exerted; fruit, 1.5 to 2 mm long, a grey-brown,
cylindrical, appressed pubescent achene, 1.5 to 2 mm long, bearing a terminal pappus of
numerous white bristles which spread apart at maturity. Weed in settled areas; pioneer in
recently mined areas. 2, 3(5861 l), 4(118N), 5(67), 6, 7, 8(9538).
Wedelia trilobata (L.) Hitchc.
syn. Silphium trilobatum L.
" wedelia"
Recent introduction. Trop. America. Occasional. Perennial creeping herb,
reaching a thickness (height) of about 40 to 70 cm; leaves, 2.5 to 7 cm long, bright
green, simple, opposite, three-lobed to lanceolate, toothed; petioles, short, extremely-
winged, or lacking, clasping the stem; flowerheads, about 2 to 2.6 cm in diameter, daisy-
like, solitary, on slender peduncles, about 5 to 7 cm long; involucral bracts, 6 to 9 mm
long, green, lanceolate, 2-ranked, 5 short inner and 5 longer outer bracts; ray-florets,
about 1 cm or longer and 0.5 cm wide, 8 to 10 in number, bright yellow; disc-florets,
about 8 mm long, light yellow, tubular, 20 to 30 in number, fruit, not seen. Planted
ornamental groundcover. 3(58609), 5, 6(237), 7.
Zinnia elegans Jacq. "zinnia"
Recent introduction. Mexico. Erect annual herb, up to 60 cm tall, stems branched;
leaves, 2.5 to 14 cm long and 1.5 to 6 cm wide, opposite, ovate to elliptic or oblong,
obtuse or acute, hispid, sessile; flowerheads, 3 to 8 cm in diameter, solitary, showy,
developing at stem and branch tips; involucral bracts, about 1 cm long, chaffy, in about
3-ranks; ray-florets, about 2 cm long and 1 cm wide, 14 to 20 in number, pistillate,
violet, pink, orange, yellow or white; receptacle, convex, paleaceous, bearing numerous
5-lobed central disc-florets, about 5 mm long, yellow; fruit, 3-angled, compressed
achene, with 1 to 3 terminal awns. Planted ornamental. 5(128), 6.