Plant slender, 8—10 inches high with one leaf near the base, varying from nearly orbicular to oval, 1½—3 inches long, 1—2 inches wide, sheathing at the base. Spike 2—8 flowered; flowers half an inch or more long; lateral sepals spreading, somewhat longer than the petals, petals and sepals oval, rose-colour; lip white, purple-spotted, longer than the petals, three-lobed, the middle longest, dilated and two-lobed or notched at the tip; spur slender, shorter than the lip. This beautiful little orchid is abundant throughout the Rockies in cool mossy spots and rich woods; flowering in June. [Illustration: _a_ Cytherea bulbosa (L.) House. (¾ Nat.) Calypso. _b_ Orchis rotundifolia Pursh. Small Round-Leaved Orchid.] [Sidenote: =Lysiella obtusata= (Pursh.) Rydb. _Small Northern Bog-orchid._] Plant 6—8 inches high from a short thick rootstock; stem naked with a single obovate or oblong leaf at the base 1½—2½ inches long, ½—1½ inches wide, obtuse. Flowers few in a slender spike, yellowish-green; upper sepal round, ovate, erect, surrounding the broad column; lateral sepals reflexed and spreading; petals lanceolate, smaller; lip entire, linear-lanceolate, and deflexed; spur slightly curved especially at the tip, shorter than the ovary. Frequent throughout the Rockies in the lower valleys, in cool shaded spots growing in moss, on the borders of streams, ponds, or lakes; flowering in June. [Sidenote: =Ophrys nephrophylla= Rydb. _Heart-shaped Twayblade._] Stem slender and smooth, 3—8 inches high. Leaves sessile, cordate or broadly ovate, ½—1 inch long; head of flowers rather loose, ½—2 inches long, 4—20-flowered; flowers very minute, purplish or greenish; sepals ovate; petals oblong, about ¹/₁₆ of an inch long; lip two-cleft, twice as long as the petals, the segments linear or hair-like. This diminutive orchid is one of the commonest species throughout the region in early summer, growing abundantly in mossy places in the moist woods, frequently not rising more than an inch or two above the surface of the ground; the flowers varying greatly in color from yellowish green to purple. [Sidenote: =Ophrys convallarioides= (Sw.) Wight. _Broad-lipped Twayblade._] Stem rather stout, 4—10 inches high, glandular-hairy above the leaves. Leaves smooth, round, oval or ovate, obtuse, 3—9 nerved, 1—2½ inches long, ½—1½ inches wide. Flowers 3—12 in a loose head, yellowish-green, ½ an inch long; bracts nearly ¼ of an inch long; sepals and petals narrow and strongly reflexed in flower, much shorter than the lip; lip nearly half an inch long, broadly wedge-shaped with two obtuse lobes at the apex and with a tooth at each side of the narrow base; column elongated but shorter than the lip, and incurved with two short projecting wings above the anther. In hemlock woods throughout the Selkirks; flowering in July. [Sidenote: =Ophrys borealis= (Morong). _Northern Twayblade._]