201. Carex atratiformis Britton, Bull. Torrey Bot. Club. 22: 222. 1895.
Carex ovata Rudge, Trans. Linn. Soc. London 7: 96, plate 9, fig. 1. 1804, not Burman f. 1768; C. atrata Linnaeus subsp. atratiformis (Britton) Kükenthal; C. atratiformis subsp. raymondii (Calder) A. E. Porsild; C. raymondii Calder
Plants loosely cespitose. Culms 20–70 cm, distally finely scabrous. Leaves 2.5–5 mm wide. Inflorescences: proximal bracts shorter than or exceeding inflorescences; spikes distinct, spreading or the proximal pendent and often separate, elongate, 10–25 × 5–8 mm; lateral 3–6 spikes pistillate, long-pendunculate; terminal spike gynecandrous. Pistillate scales light to dark brown with hyaline margins, lanceolate, longer than and as broad as perigynia, midvein same color as body, inconspicuous or lighter in color, conspicuous, raised, prominent, sometimes short-mucronate. Perigynia ascending, yellow brown or chestnut, veinless, ovate or elliptic, 2.5–3 × 1.5–1.75 mm, apex abruptly beaked, distally papillose; beak 0.4–0.5 mm, bidentate, smooth. Achenes filling proximal 1/2 or less of perigynia.
Fruiting Jun–Aug. Forest margins, open woodlands, calcareous ledges, stream banks, lakeshores, wet cliffs, high elevation seeps; 10–1500 m; Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Ont., Que., Sask., Yukon; Alaska, Maine, Mich., N.H., N.Y., Vt.
Carex raymondii is a minor variant consisting of specimens with yellow-brown perigynia and light brown scales with midribs lighter in color than the bodies of the scales. The hybrid taxon Carex ×quirponensis Fernald (= C. atratiformis × C. norvegica) is known from Newfoundland and Quebec.