ORDER 138. ORCHID ACE^E. 681 



TRIBES AND GENERA. 



CYPRIPEDIE J2. Anthers 2, fertile, the 3rd a petal-like appendage over tlio 



stigma. Lip a large, inflated spurless sack 

 OPIIRYDE jE, &e. Anther only 1, terminal or dorsal on the stigma. (*) 



* Lip produced behind into a spul- which is free from the ovary, (a) 



a Anther erect, terminal ; pollinia 2, granular, pedicellate and attached to as 

 many glands on the stigma, which glands are (b) 



b concealed ia a pouch (Flowers large, rose-colored, lip entire) in ORCHIS. 2 



b naked and close together (Flowers small, lip entire or toothed) in...GYMNADEMA. 3 

 b naked and widely separated (Lip entire or lobed, or cleft or fringed.) PLATANTHERA. 4 



a Anther bont over the end of the stigma like a lid. Pollinia 4 TIPULARIA. 5 



* Lip not produced into a spur behind, or the spur is adnate to the ovary, (c) 



C Lip a large, inflated sack with 2 spur-like points lelow the apex CALYPSO. 6 



C Lip not saccate. Plants brown, leafless, or with radical leaf, (d) 



d Lip hooded, i. e., its margins involute. Pollinia 8. Fls. expanding. BLETIA. 7 



d Lip concave, sessile, often with an adnate spur. Pollinia 4. ..CORALLORHIZRA. 8 

 d Lip concave, raised on a claw. Pollinia 4. Plant with 1 late leaf. ..APLECTBUM. 9 

 C Lip not saccate. Plants green and with leaves, (e) 



e Lip flat. Flowers obscure, in racemes nearly bractless. (f ) 



f Lip entire, dilated ; Column minute. (Leaf 1.) MYCROSTYLIS. 10 



f Lip sagittate or cordate. Column lengthened. Leaves 2 LIPPAEIS, 11 



f Lip 2-lobed or cleft at apex. Lvs. 2, cauline opposite LISTEEA. J3 



6 Lip channeled, recurved. Fls. whitish, in bracted spikes, (g) 



g Sepals reflexed. Lip arched and recurved, 3-lobcd CRANICHIS. 13 



g Sepals erect. Lip ascending, embracing the column SPIEANTHES. 14 



Lip gibbous beneath, pointed at apex GOODYEBA. J5 



e Lip bearded or 3-lobed. Stamen lid-like. Flowers showy, (h) 



h. Flowers several, purple, with .a bearded lip posterior CALOPOGOX. 10 



h. Flowers with the lip anterior (as in the order generally), (k) 



k Column free from the lip, clavate. Fls. purplish POGONIA. 17 



k Column adherent to the tip below. Fls. purple ARETHUSA. 18 



k Column adherent to the lip. Fls. yellow. On trees EPIDENDRUM. 19 



1. CYPRIPE'DIUM, L. LADY'S SLIPPER. (Gr. Kvnpig, Venus, 

 irodiov, a slipper ; from the slipper-like form of the lip.) The 2 lower 

 sepals united into 1 segment, or rarely distinct ; petals spreading ; lip 

 inflated, saccate, obtuse ; column terminated by a petaloid lobe (barren 

 stamen) and bearing a 2-celled anther under each wing. Fls. large, 

 very showy, distinguished for the large, inflated lower petal or lip ; Ivs. 

 large, plaited, veined. 



Sepals 2, the lower compound of 2 united either wholly or near the tip. (*) 



* Stem leafy. Flowers 1 to 3, mostly but 1, yellow Nos. 1, 2 



Flowers solitary or several, white or rose-colored Nos. 8, 4 



* Stem a leafless scape, 2-leaved at base. Flower rose-colored No. 5 



Sepals 3, the 2 lower entirely distinct No. 6 



1 C. piibescens Swartz. LARGE YELLOW LADIES SLIPPER. St. leafy, Ivs. 

 broad-lanceolate, acuminate; sepals lanceolate; lip shorter than the linear, twisted 

 petals, compressed laterally, convex both above and below ; sterile stamen triangular, 

 acute ; plant pubescent. Woods and meadows, Can. to Wis., S. to Ga. Sts. usu- 

 ally several from the same root, If or more high. Lvs. 3 to 6' by 2 to 3, many- 

 veined, clasping at base. Flower mostly solitary. Segm. 4, greenish with 

 purple stripes and spots, the lower bifid, composed of 2 united sepals, the lateral 

 2 to 3' by 3", wavy and twisted. Lip moccasin-shape^ bright-yellow, spotted 

 inside, with a roundish aperture. May, Jn. 



2 C. parviflorum Salish. SMALLER YELLOW LADIES' SLIPPER. St. leafy ; Ivs. lan- 

 ceolate-acuminate j sep. ovate or lance-ovate ; lip shorter than the petals, compressed 

 from above and bancath; sterile stamen triangular, acute; plant pubescent. In 

 low woods and prairies, Can. to Wis. and Ga. (Miss Wyman). More common 

 westward. Plant 8 to 12' high, rarely taller, very leafy. Flower a third smaller 

 than in No. 1. Petals 1 to 18", twisted or not. Upper sep. broadest. Lip evi- 

 dently flattened on the upper side, convex laterally, dull yellow. May, Ju. 



