ORCHIDACEAE. 303 



5. Peramium Menziesii (Lindl.) Morong. MENZIES' RATTLESNAKE 

 TAIN. (I. F. f. 1133.) Scape stout, 2-4 dm. high, glandular-pubescent. Leaves 

 ovate-lanceolate, 4-6 cm. long, 1 5-30 mm. wide, the blade acute at both ends, often 

 without white blotches or reticulations ; spike not i-sided ; flowers 7-9 mm. long ; 

 gaiea concave, ovate-lanceolate, the tip long, usually recurved; lip swollen at the 

 base ; anther ovate, pointed, on the base of the column, which is prolonged above 

 the stigma into a gland-bearing awl-shaped beak. In woods, Quebec to Br. Col., 

 N. H., N. Y., Minn., Ariz., and Cal. Aug. 



20. ACHROANTHES Raf. [MICROSTYLIS Nutt.] 



Low herbs, from a solid bulb, our species I -leaved, and with i-several scales 

 at the base of the stem. Flowers small, white or green, in a terminal raceme. 

 Sepals spreading, separate, the lateral ones equal at the base. Petals filiform or 

 linear, spreading. Lip cordate or eared at the base, embracing the column. 

 Anther erect between the auricles, 2-celled ; pollinia 4, smooth and waxy, 2 in 

 each sac, the pairs cohering at the summit, without caudicles or glands. Cap- 

 sule oval, sometimes nearly globose, beakless. [Greek, in allusion to the green 

 flowers?] About 40 species, widely distributed. Besides the following, about 4 

 others occur in the southern and western parts of North America. 



Leaf sheathing the base of the stem. i. A. monophylla. 



Leaf clasping the stem near the middle. 2. A. unifolia. 



1. Achroanthes monophylla (L.) Greene. WHITE ADDER'S-MOUTII. (I. F. f. 



1134.) Stem slender, 10-15 cm. high, smooth, glabrous, striate. Leaf sheathing 

 the stem at its base, the blade 2-5 cm. long, 1-4 cm. wide ; raceme 2-7 cm long, 

 narrow, 6-io mm. thick ; flowers whitish, about 2 mm. long ; pedicels nearly 

 erect, bracted, 2-4 mm. long ; sepals acute ; lip triangular or ovate, acuminate, 

 the lateral lobes obtuse ; capsule oval, about 6 mm. long. In woods, Quebec to Minn., 

 Penn., and Neb. July. 



2. Achroanthes unifolia (Michx.) Raf. GREEN ADDER'S-MOUTH. (I. F. f. 

 1135.) Stem glabrous, striate, 10-25 cm. high. Leaf clasping the stem near the 

 middle, oval or nearly orbicular, 2-5 cm. long ; raceme 2-7 cm. long, sometimes 

 2 cm. thick ; flowers greenish, about 2 mm. long, the pedicels very slender, 

 spreading, 6-10 mm. long ; sepals oblong ; lip broad, 2-lobed at the apex, with a 

 small tooth in the sinus ; capsule oval or subglobose. In woods and thickets, 

 Newf. to Ont. and Minn., south to Fla., Ala. and Mo. July. 



21. LEPTORCHIS Thouars. [LIPARIS Rich.] 



Low herbs, with solid bulbs, the base of the stem sheathed by several scales and 

 2 broad shining leaves. Flowers in terminal racemes. Sepals and petals nearly 

 equal, linear, spreading, petals usually very narrow. Column elongated, incurved, 

 thickened and margined above. Pollinia 2 in each sac of the anther, smooth and 

 waxy, the pairs slightly united, without stalk, threads or glands. Lip nearly flat, 

 often bearing 2 tubercles above the base. [Greek, signifying a slender orchid.] 

 About loo species, widely distributed in temperate and tropical regions; only the 

 following known to occur in North America: 



Raceme many-flowered ; lip as long as the petals. i. L, liliifolia. 



Raceme few-flowered ; lip shorter than the petals. 2. L. Loeselii. 



1. Leptorchis liliifolia (L.) Kuntze. LARGE TWAYBLADE. (I. F. f. 1136.) 

 Scape 1-2.5 dm. hig n > 5-10- striate. Leaves ovate or oval, 5-12 cm. long, obtuse, 

 keeled below, the sheaths large and loose. Raceme sometimes 15 cm. long; flowers 

 numerous, showy; petals very narrow or thread-like; lip erect, large, 10-12 mm. 

 long, about as long as the petals, wedge-obovate; column 3 mm. long, incurved, 

 dilated at the summit; capsule somewhat club-shaped, about 12 mm. long, the 

 pedicel thickened in fruit. In moist woods and thickets, Me. to Minn., Ga. and 

 Mo. May-July. 



2. Leptorchis Loeselii (L.) MacM. FEN ORCHIS. LOESEL'S TWAYBLADE. 

 (T. F. f. 1137.) Scape 5-20 cm. high, strongly 5-7-ribbed. Leaves elliptic or 



