ORDER 137. ORCHIDACE.E. 325 



3. VALLISNERIA, Mich. EEL-GRASS. Fls. $ ? . Spathe ovate, 2- 

 i-parted. $ Spadix or spike covered with minute naked fls. 9 Fl. soli- 

 tary, a slender perianth with linear segm. and 3 bifid stig. Fr. cylindrical, 



00 - seeded. V ? Fertile powers on long spiral scapes. July, Aug. 



V. ftplralis L. Lvs. 1 2f long, obtuse, \' wide, scapes of the sterile plants short, > r 

 the fertile filiform, tortuous, 2 If, bearing the single white fl. at or near the surface 



ORDER CXXXVI. BUKMANNIACE.E. 



Small annual herbs, with naked or scaly stems and scale-like tufted leaven. 

 Flowers perfect. Perianth tubular, 6-toothed, adherent. Stamens 3 or fi. 

 Capsule 1- or 3-celled. Seeds oo, minute, in a loose testa. 



1. APTERIA, N. Perianth tube longer than the slender teeth, which 

 are alternately narrower. Caps, globular, 1-celled. Apparently leafless. 



A. setaeea N. Erect, very slender, 4 6f, with remote subulate scales, and bearing 

 above 1 or 2 racemes ; flowers 3 4", purplish, distant. Woods, Fla., and W. 



2. BURMANNIA, L. Perianth tube scarcely produced above the 

 ovary, often 3-wSnged below, limb with the 3 inner teeth much shorter 

 Capsule prismatic, often 3-winged, 3-celled. @ Leafless. 



1 B. blflora L. Stems capillary, simple, 2 3', with scarcely perceptible bracts, and 



1 or 2 (rarely more) light-blue flowers, 2 3" long at top. Swamps, Va., and 8. Oct. 



2 B. capltata (L). Stem setaceous, 6 8', simple, bearing at top a dense cluster of- 



white flowers, and a few subulate bracts. Uplands, S. : less common. Sept. 



ORDER CXXXVII. ORCHIDACE^E. ORCHIDS. 



Herbs perennial with fleshy roots, simple, entire, parallel-veined leaves. 

 Flowers veiy irregular, with an adherent, ringent perianth of 6 parts. Sepals 

 3, usually colored. Petals 3, odd one (lowest by the twisting of the ovary), 

 called the lip, diverse in form from the others, sometimes lobed, often spur- 

 red. Stamens 3, gynandrous (consolidated with the style), some of them 

 abortive, pollen powdery or waxy. Ovary inferior, 1-celled, capsule 3-valved. 

 Seeds innumerable. Figs. 71, 105, 340, 247, b. 263, 291, 435. 



( CYPRIPEDIE.fl5. Anthers, the 2 lateral fertile, the terminal petaloid. . .(a) 



a Lip a large, inflated, spurless sac. Petals and sepals spreading CTPKIPEDIUM. 1 



( OPHRYDE^E, Ac. Anthers, only the upper one fertile, 2-celied...(6) 



b Lip a large inflated sac, 2-spu rred under the apex. Lenf 1 CALYPSO. ' 



6 Lip produced behind into a spur, which is free from the ovary... (c) 

 b Lip spurless, or the spur adheres to the ovary (except in fvo. 13)... (J) 



c Anther fixed ; pollen-masses 2, club-shaped, in 2 separate cells ORCHIS. 3 



< Anther lid-like, on the end of the stigma : p >llen-masses 1 TIFULJ Rn < 



d Plants brown and leafless, rarely with radical leaves. . .(e) 

 d Plants green and (except No. 16) furnished with leaves... (m) 



a Lip hooded, '. e., its margins involute. Perianth spreading BLKTIA. S 



t Lip concave, sessile, often with an adnate cpur OOKALLOKUIZI 6 



t Lip concave, raised on a claw. Plant with 1 late leaf APLKCTBUK. 1 



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



in Lip Sat, expanded and lobed, tubercled at base. Flowers showy OMClOlim. S 



Lip channelled, reflexed Flowers whitish, in bracted spikes. . .(o) 

 m Lip bearded or 3-lobed. Stamen lid-like. Flowers showy... (x* 



