202 



ORDER CXXIII. ALISMACE.E WATER-PL ANT AIN-FAM. ORDER CXXV. ORCHTDACE^E ORCHIS-FAM, 



5. P. perfoliatus. Clasping Pond-weed. 



Stem branching dichotomously ; leaves alternate, ovate or lance-ovate, 

 sometimes broad-ovate, obtuse, cordate and clasping at base ; spike purplish, 

 loosely-flowered, OD a short peduncle. A common species in stagnant waters, 

 distinguished by its almost perforate leaves. Stem varying in length accord- 

 ing to the depth of water. July Aug. 



ORDER CXXIII. Alismacese. Water- 

 Plantain-family. 



1. ALlSMA. 



Flowers perfect. Stamens 6. Ovaries numerous, arranged 

 in a circle. Achenia compressed, coriaceous. 



1. A. Plantago. Water Plantain. 



Leaves oval or ovate, varying to oblong, or even lanceolate, acuminate, on 

 long petioles, 8 9-nerved ; flowers in a loose, verticillately -branching panicle ; 

 petals small, deciduous, white, with a purplish tinge, longer than the green 

 sepals. A very common plant in wet grounds, with smooth leaves somewhat 

 resembling those of the common Plantain. The scape terminates in a long, 

 compound panicle, and grows 12 ft high. July Aug. Per. 



2. SAGITTARIA. 



Flowers monoecious, rarely dioecious. Stamens numerous. 

 Ovaries many, aggregated in a spherical head, and forming in 

 fruit a globose head of compressed, winged achenia. Per. 



1. S. sagittifolia. Arrowhead. 



Scape simple, sheathed at base by the petioles, acaulescent ; flowers in ver- 

 ticils of 3; sterile ones at the summit of the scape, fertile ones below; petals 

 white; leaves extremely variable, generally triangular with sagittate lobes, 

 varying from very broad to very narrow. In this state the scape is 12 ft 

 high, and the petioles nearly as long. In other forms, which grow especially 

 in muddy grounds that are frequently overflowed, the leaves are oval or oblong, 

 with thick, spongy petioles, and sometimes nothing but petioles. In this state 

 the plant is 3' 12' high, with the petioles and scape often very large and thick 

 for the size of the plant Again, the leaves are linear, and the scape and peti- 

 oles very slender. The height of this variety varies from 2' 12'. Common 

 in wet grounds. June July. 



8. TRIGL6CHIN. 



Sepals and petals nearly alike, concave, greenish, deciduous. 

 Stamens 6. Filaments very short. Anthers large, oval. Pistils 

 3 6, forming a compound ovary of 36 cells. Stigmas sessile. 

 Capsule clavate, dividing at length into 3 6 indehiscent, 1- 

 seeded carpels. 



1. T. maritimum. Arrow-grass. 



Scape naked, fleshy, angled; leaves very narrowly linear, fleshy, semi- 

 cylindric, shorter than the scape ; flowers small, green, pedicellate, arranged in 

 a long, loose raceme, destitute of bracts; fruit ovate, composed of 6 carpels, 

 rounded at base. A little rush -like plant, common in salt marshes. Scapes 

 8' 15' high, arising from creeping rhizomas. Aug. Per. 



ORDER CXXV. Orchid acese. Orchis-family. 



SYNOPSIS OF THE GENERA. 



* Lip with a spur at base distinct from the ovary. 



8. ORCHIS. Anther-cells parallel. Pollen-granules united to form 2 large 

 masses attached by pedicels to the glands of the stigma, which are inclosed in a 

 little hood. Flowers on a scape. 



4. GYMNADENIA. Anther-cells parallel. Pollen-masses 2, pedicellate, at- 

 tached to the 2 glands of the stigma, which are not inclosed in any hood or 

 covering. Stern leafy. 



5. PLATANTHERA. Anther-cells divergent at base. Pollen-masses pedicel- 

 late, attached to the 2 glands of the stigma, which are not inclosed in a hood. 

 Stem leafy. 



** Lip not inflated. Spur mostly absent, when 

 present cohering' to the top of the ovary. 

 t Lip not bearded. 



1. LIPARIS. Petals linear or filiform. Spur none. Pollen-masses 4, paral- 

 lel. Leaves 2, at base of the scape. 



2. CoRAtLoRirizA. Petals nearlv oblong. Lip usually with a short spui 

 adherent to the top of the ovary. Pollen-masses 4, oblique. Plants destitute 

 of green herbage. 



9. SPIEANTHI 8. Lip tapering to a short claw, and furnished with 2 callous 

 processes just above the claw. Column arching, on a short, oblique pedicel. 

 Pollen-masses 2. Flowers mostly in spiral spikes. 



10. GOODYERA. Lip sessile, saccate at base, entire. Column straight. Pol- 

 len-masses 2. Leaves reticulated. 



tt Lip bearded. 



6. ARETHUSA. Sepals and petals united at base. Lip on the lower side of 

 the flower. Pollen-masses 4, 2 in each of the 2 anther-cells, made up of little 

 grains. Scape mostly leafless in flower, afterward 1 -leaved. 



7. POOONIA. Petals and sepals distinct at base. Lip on the lower side of 

 the flower. Column not winged at apex. Pollen-masses 2, 1 in each cell, fari' 

 naceous. 



8. CALOPOOON. Petals and sepals distinct at base. Lip on the upper side 

 of the flower, bearded near the summit, tapering to a claw. Column winged at 

 apex. Leaf 1, grass-like. 



*** Lip inflated. 



11. CYPREPEDITM. Lip a large, inflated, reticulated sac. 



1. LiPARIS. 



Sepals nearly equalling the petals. Petals linear, or filiform. 

 Lip spreading, flat. Column elongated, winged at apex, in- 

 curved. Pollen-masses 4, parallel to each other. 



1. L. lilifolia. 



Tway-Uade. 



Acaulescent; leaves 2, ovate, sheathing at base; petals filiform, reflexed; 

 lip obovate, abruptly acute, large, brownish-purple. A low plant, with a sim 

 pie scape arising from a solid bulb, and bearing a slender raceme of a few rather 

 large, purplish flowers. Scape 2' 5' high. Not rare in moist woods, especially 

 in the Middle States. June. 



2. CORALLORHtZA. 



Sepals and petals nearly equal ; lateral ones erect ; upper 

 vaulted. Lips spreading and recurved, usually produced behind 

 into a short spur, which adheres to the top of the ovary. Pollen- 

 masses 4, oblique to each other. Leafless. 



1. C. multiflora. Coral-root. 



Scape many-flowered ; lip cuneate, oval, 3-lobed, spotted with bright pur- 

 ple; middle lobe recurved, much longer than the lateral, tooth-like lobes; spur 

 conspicuous; capsule and ovary obloug. A curious, leafless plant, 12' 18' 

 high, with a brownish-purple scape, furnished with a few bracts and rather 

 large, brownish flowers. The scape arises from a creeping, very branching and 

 much-toothed rhizoma, resembling somewhat pieces of coral. Common in rich 

 woods ; probably parasitic on the roots of trees. July Aug. 



3. ORCHIS. 



Flower ringent. Sepals and petals nearly equal, most of them 

 converging and vaulted. Lip depressed, attached to the base ol 

 the column, and terminating in a spur distinct from the ovary. 

 Anthers all parallel, close together. Pollen in small grains com- 

 bined in 2 large masses, each pedicellate, and attached to the 

 base of the 2 glands of the stigma, which are both inclosed in a 

 little covering, or hood. 



1. 0. spectabilis. 



Showy Orchis. 



Acaulescent ; scape low, with about 5 acute angles ; leaves few, mostly 2, 

 nearly as long as the scape, oblong-obovate, somewhat thick in texture, of a 

 shining green ; flowers large, few, showy ; bracts lanceolate, acute, large and 

 leaf-like ; petals and sepals arched, mostly pink, rarely white ; lip white, en- 

 tire ; spur obtuse, white. A very pretty and showy little plant, 8' high, com- 

 mon in rich, rocky woods. May. 



4. GYMNADfcNIA. 



Flower ringent. Sepals and petals nearly equal, mostly con- 

 verging and vaulted. Lip depressed, attached to the base of the 

 column, terminating in a spur distinct from the ovary. Anther- 

 cells parallel. Pollen-masses 2, pedicellate, attached to the 2 

 glands of the stigma, which are naked, and not contained in any 

 covering. 



1. Gr. tridentata 



Naked Orchis. 



Stem slender, bearing a comparatively large, oblong or oblong-ovate, obtuse 

 leaf toward the base, and several smaller ones resembling bracts above ; flowers 

 small, greenish, rather numerous, Jn a short, oblong spike ; lip truncate, 8- 

 toothed, cuneate-oblong; spur slender, curved upward, clavate, longer than 

 the ovary. A slender plant, distinguished by Its sinjrlo, large, nearly radical 



