Arctanthemum arcticum subsp. arcticum

Leucanthemum arcticum (L.) DC. Prodr. 6: 45. 1837
Chrysanthemum arcticum L. Sp. PI. 889. 1753.
Matricaria arclica Desr. in Lam. Encyc. 3: 735. 1791.
Tanacelum arcticum Schultz-Bip. Tanac. 35. 1844.
Chrysanthemum Gvielini Ledeb. Fl. Ross. 2: 541. 1845.
Leucanthemum adustum Fisch.; Herder, Bull. Soc. Nat. Mosc. 38: 415, as synonym. 1865.
A low perennial, with a rootstock; stem 1-3 dm. high, glabrous, or slightly villous above; leaves fleshy, glabrous, all except the uppermost cuneate or obovate-spatulate; lower leaves distinctly petioled, coarsely dentate or lobed, sometimes 3-cleft, the middle stem-leaves short-petioled, often 3-lobed, the upper ones sometimes entire and linear; heads solitary at the end of the stems; involucre saucer-shaped, 7-8 mm. high, 10-20 mm broad, slightly villous at the base; bracts in 3 series, brownish, with broad, almost black, erose, scarious margins, the outer oblong, the inner elliptic; ray-flowers 15-25; ligules white, 10-13 mm. long, about 3 mm. wide; disk-corollas yellow, 3 mm. long; tube thicker than the achenes, equaling the elongatefunnelform throat; lobes lance-ovate; achenes subcylindric, sHghtly 10-ribbed, glabrous, 2 mm. long; pappus wanting.
Type locality: Kamchatka.
Distribution: Arctic America from Hudson Bay to Alaska; also Siberia and Russia.