I. Helenium: stem 3-4 feet high, round, furrowed, solid, leafy, branched above; leaves unequally dentate, downy beneath, cordate-ovate, acute, clasping, the root-leaves stalked elliptic-oblong; heads few together or solitary, terminal, very large, the florets bright yellow. - Elecampane. - Moist pastures. Fl. July to September.

I. Conyza: stem 1-2 feet high, leafy; leaves ovate-lanceolate, downy, denticulate, the lower ones narrowed into a footstalk; heads corymbose, the florets yellow, those of the circumference between tubular and ligulate, with a short ligule on the inner side. - Plowman's Spikenard. - Calcareous soils. Fl. July to September.