ORDER 138. ORCHIDACE^E. 683 



2 Cr. tridentata Lindl. St. slender ; lowest leaf linear-oblong or oblanceolate, ob- 

 tuse, the others 3 or 4, very small and bract-like; fls. 7 to 12, sessile, in a short, 

 open spike ; sep. obtuse, erect<spreading ; lip a little longer, truncate and 3-toothed 

 at the apex, produced behind into a slender, often clavellate spur which is longer 

 than the ovary.' In damp woods, Can. and U. S. Root a few thick fibers. St. 

 12 to 18' high, leaf about G', bracts 1' and less. Spike often as wide as long, 

 With small, greenish-white fls. Spur 4 or 6" long, usually curved. Jn., Jl. (0. 

 tridentata Willd.) 



3. CLAVELLA* A has the fls. more diverging and the spur conspicuously club- 

 shaped. South. 



3 O. flava Lindl. St. flexuous, leafy ; lower Ivs. narrow-lanceolate, acute, upper 

 gradually smaller ; spike densely many-flowered ; lip (ytllow) ovate, crenulate or 

 somewhat wavy, longer than the broad-ovate, obtuse sepals, shorter than the sub- 

 ulate spur. Swamps, in pine barrens, X. J. to Ga. and La. Et. of thickened 

 fibres. St. 12 to 15' high, with Ivs. nearly as long as the internodes. Spike 

 globular or oblong, with 30 to 50 small, orange-colored fls. Sep. about 1" long, 

 spur nearly 3", lip 2". Jti., JL (0. flava and iiigra Xutt.) 



4. PLATAN 'THERA, Richard. ORCHIS. (Gr. -Aarvr, broad, dv6r/pd, 

 anther.) Anther cells diverging below, and the two glands to which 

 the pedicellate pollinia are attached widely separated. Otherwise as in 

 Orchis. (Platanthera and Gymnadenui are separated from Orchis by 

 characters purely artificial, and should be reunited with it.) 



* Leaf only one. Flowers greenish^white. Lip entire or 8-lobed Nos. 1, 2 



* Leaves only two. roundish, large. Flowers grecni.sh. Lip entire. .Nos. 3, 4 



* Leaves several, clothing the stem more or less, (a) 



a Lip undivided and entire, neither fringed, lobed, nor toothed, whitish Kos. 5, C 



a Lip undivided, but 3-toothed, not fringed. Flowers yellowish Nos. 7, 8 



but frinzed. Flowers" bright yellow or white Nos. 91 1 



a Lip 3-parted, segments fringed. Flo wers'white or greenish Nos. 12, 13 



segments fringed. Flowers purple Nos. 14. 15 



segments merely toothed, terminal one 2-lobed. Fls, purple No.' 1 1 



segments entire, long, linear-setaceous. Whitish Nos. IT, 13 



1 P. obtusata Lindl. Lf. solitary, oblong-obovate, obtuse ; st. bearing the le;;f 

 near its base ; spike loose ; upper sep. broadest ; pet. subtriangular ; lip linear, 

 entire, with 2 tubercles at base, as long as the arcuate, acute spur. Found in 

 muddy ponds and ditches, N. H. (Storrs), N. to Lab. Stem slender, angular, 

 68' high, terminating in a thin spike of about a dozen small, greenish-white 

 flowers. Leaf tapering at base, usually obtuse at the summit, 2 3' in length, 

 and 1 in breadth, issuing with the stem from 2-^3 radical, sheathing bracts. July. 



2 P. rotundifolia Lindl. Lf. solitary, roundish-ovate ; scape naked ; spike few- 

 flowered ; bracts obtuse, shorter than the ovary ; sep. and pet obtuse ; lip 3-lobed, 

 lateral lobes subfakate, middle one obcordate ; spur as long as the lip. Ct., Penn. 

 (Eaton), Can. Scape near a foot high, slender, without a bract. Leaf 2^-4' long, 

 ^ as wide, spotted, sheathing at base. Flowers about a dozen, of a greenish- 

 white, remarkable for their broad, 3 (almost 4)-lobed, pendent lip. (0. rotund. Ph.) 



3 P. orbiculata Lindl. Lvs. 2, radical, suborbicular, rather fleshy ; scape bractc- 

 ate: upper sep. orbicular, lateral ones ovate; lip linear-subspatulate, nearly twice as 

 long as the sepals ; spur arcuate, compressed, clavate, twice as long as the ovary. 

 A remarkable plant, not uncommon in clcl woods and in thickets, Penn. to 

 Can. and W. States. Leaves lying flat upon the ground, 36' diam., rather in- 

 clining to oval or ovate with the apex acute. Scape 1 2f high, sheathed with q 

 lew bracts, bearing a raceme of numerous, greenish-white flowers. Lip 9 to 12" 

 by 1" or narrower. Spur 1 J- 2' long. Jl. (0. orbiculata Ph.) 



4 P. Hookeri Lindl. Lvs. 2, radical, suborbicular or suboval, fleshy; scape 

 jiaked; bracts lanceolate, nearly as long as the flowers; upper sepal ovate, erect, 

 lateral ones dejiexed and meeting behind: pet. acute, lip lanceolate, projecting, 

 acuminate, a little longer than the sepals ; spur subulate, arcuate, about twice 

 longer than the ovary. Woods, Can.. X. Eng. to Vis. (Lapham), rare. Resem- 

 bles 0. orbiculata, but is very distinct. Scape 812' high, without a bract be- 

 low the Mowers. Leaves 4 5' long, nearly or quite cs wide. Flowers 12 18, 



