182 
Spring Flora of Oklahoma 
Pappus-bristles surrounded by a villous white ring 
at base. IX. Sitilias. 
I. SERINIA Raf. 
Low, glaucescent, branching annual herbs. Leaves al¬ 
ternate, clasping, entire, or lobed, and few, small, long- 
peduncled heads of yellow flowers. Involucre broadly 
campanulate, its bracts about 8, equal, membranous, be¬ 
coming concave after flowering. Receptacle flat, naked. 
Rays truncate and 5-toothed. Achenes obovoid, 8-10- 
ribbed, contracted at the base, rounded at the summit. 
Pappus none. 
1. Serinia oppositifolia (Raf.) Kuntze. Serinia. Glabrous 
throughout, or slightly glandular-pubescent along the ends of the 
peduncles, branched from the base, 4'-10' high. Basal and lower 
leaves petioled, oblong-lanceolate, or spatulate in outline, entire, 
lobed or pinnatifid, 3'-5' long. Upper leaves sessile, clasping, alter¬ 
nate, usually entire. Heads broad. 
In dry soil. March-May. Common. 
II. KRIGIA Schreb. 
Small, annual or perennial herbs. Leaves mostly basal, 
toothed or lyrate. Head of yellow flowers, solitary at the 
end of the scape. Involucre campanulate, in 2 series. 
Receptacle flat, naked. Rays truncate, 5-toothed. Achenes 
turbinate, 15-20-ribbed, truncate. Pappus in 2 series, the 
outer of 5 thin, broad, rounded scales, the inner of 10 
or more slender naked bristles. 
1. Krigia virginica (L.) Willd. Carolina Dwarf Dandelion. 
Annual, acaulescent. Scapes several, l'-15' high, becoming branched 
and leafy. Leaves all basal, spatulate, lanceolate or linear, pinnat¬ 
ifid, sinuate, lobed, dentate or rarely entire, l'-6' long. Head 3"-7" 
broad. 
In dry sandy soil. April-August. 
III. CYNTHIA D. Don. 
Perennial herbs, with tufted, basal leaves, the large, 
many-flowered heads at the ends of simple or branched 
scapes. Flowers orange or yellow. Bracts of the involu- 
