Cypripedium. CXL. ORCHIDACEiE. 537 



and of a dark green, reticulated above with white veins. They are ovate, 1 — 2' 

 in length, contracted at base into winged petioles scarcely halt as long. Scape 

 erect, 6 — 12' high. Flowers wliite, in a terminal, oblong, cylindric .spike. Lip 

 roundish, saccate, inllatcd. July, Aug. 



0. rcpcns. (G. rcpcns. JJr.) Lr.s. less conspicuously reticulated ; .tpzAr some- 

 what unilateral. — A reduced lurni olG. pubescens, certainly unworthy of being 

 exalted into a species. Stem (3 — 8' high. Flowers in one row, which is more 

 or less spiral. 



13. LISTfiRA. Brown. 



Named for Dr. Murtin Lister, an English naturalist, died 1711. 



Lip 2-lobod, pendant, with no callous processes ; column wingless, 

 minute ; anther fixed by its base, persistent. 



1. L. coRDATA. Br. (Ophris. ATx.) Ticaij-blade. 



St. 2-leaved, the leaves opposite, deltoid-su'bcordate, acute ; roc. few-flow- 

 ered; lip linear, 2-toothed at base, deeply bifid, with divaricate and acute seg- 

 ments; C('/i/;/iM very short. — Root fibrous. Stem 4 — 8' high, furrowed. Leaves 

 i — f diam., sessile, about half way up the stem. Flowers minute, greeni.sh- 

 purple, 10 — 15, in a short raceme. A delicate little plant, in woods and sphag- 

 nous swamps, among mountains, &c., N. States and Brit. Am. July, Aug. 



2. L. coNVALLARiolDEs. Nutt. (Epipactis. Sw.) 



St. 2-leaved, the leaves opposite, roundish-ovate ; rac. few-flowered, loose, 

 pubescent; scp. ovate-lanceolate; lip oblong, 2-toothed at ba.se, with 2 roundish 

 lobes and an intermediate minute one at the apex ; coluvin elongated. — Car. to 

 Arc. Am. Root fibrous. Stem very slender, 5 — 10' high, sheathed with a few 

 bracts bearing the 2 leaves near the middle. Leaves near an inch long, f as 

 wide. Flowers small, the broad, obcordate lip twice as long as the sepals. May. 



Section 4. Lateral anthers fertile ; the middle one sterile and pe- 



taloid. 



14. CYPRIPEDIUM. 



Gr. KDTrpjf, Venus, ttoSlov, a slipper; from the slipper-like form of the lip. 



The 2 lower sepals united into 1 segment, or rarely, distinct ; lip 

 ventricose, inflated, saccate, obtuse ; column terminated by a peta- 

 loid lobe (barren stamen). — Fls. large ^ very showy ^ distinguished for 

 the large, injiated lower petal or lip. 



1. C. CANDiDUM. Willd. Wkife-flowercd Ladies' -slifper. 



St. leafy ; lis. oblong-lanceolate ; /. terminal, solitary ; sep. elliptic- 

 lanceolate, acuminate, lower scarcely bifid at apex ; pet. lance-linear, longer 

 than the compressed lip ; loI)c of the style lanceolate, rather obtuse. — Borders 

 of woods, prairies, Penn. to Ind. Plummer! Resembles the next in foliage, but 

 remarkably distinguished by the white flow^er. Stem about If high, simple. 

 Leaves 3 — 6' by 1 — 1^', sheathing the stem, acute. Ovary pedicellate. Lip 1' 

 in length. Petals and sepals nearly 2'. May. 



2. C. ACAULE. Ait. (C. humile. Sw. 1) Acaulescent Ladies' -slipper. 

 Scape leafless, 1-flowered ; Ivs. 2, radical, elliptic-oblong, rather acute ; 



lobe of the column roundish-rhomboidal, acuminate, deflexed ; jvc^. lanceolate; 

 lip longer than the petals, cleft before.— A beautiful plant, in dark woods, Car. 

 to Arc. Am. Leaves large, plaited and downy. Scape 10 — 14' high, with a 

 single lanceolate bract at the base of the large, solitary flower. Sepals i' long, 

 the two lower completely united into a broad lanceolate one beneath the lip. 

 Petals lateral, wavy. Lip 2' by 1', purple, forming the most showy part of the 

 flower. May, June. 



3. C. PARViFLORLM. Salisb. Yellow Ladies' -slipper. 



St. Leafy; Ivs. broad-lanceolate, acuminate; lobe of the column triangular- 

 oblong, acute ; scp. ovate, oblong, acuminate ; pet. long, linear, contorted ; lip 

 shorter than the petals, compres.sed. — Woods and meadows, Newf. to Car. 

 Stems usually several from the same root, about a foot high. Leaves 3 — 6' 



