Fam. 41. Orchidaceae Juss. Orchid Family 



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Perennial herbs of various habits and habitats, terrestrial, semiaquatic or epi- 

 phytic, autophytic or saprophytic, hermaphroditic, produced from a short or 

 elongated (rarely) coralloid rhizome; roots subterranean or aerial, fibrous, fleshy 

 or tuberous, fasciculate or adventitious and scattered on the rhizome or stem; stems 

 terete, much-abbreviated to elongated, slender to very stout, naked, bracteate or 

 leafy; leaves simple, radical or cauline or both, persistent, deciduous or fugacious, 

 occasionally altogether lacking, varying from sheathing bracts to a broad or 

 narrow lamina; lamina linear to broadly elliptic, membranaceous to somewhat 

 fleshy; inflorescence terminal, supported by an abbreviated to greatly elongated 

 peduncle, composed of one or more flowers, commonly a spike or simple raceme; 

 flowers small and inconspicuous to rather showy, zygomorphic, perfect; perianth 

 composed of three outer segments (sepals) and three inner segments (petals), the 

 segments free or more or less united, adnate to the 1- or 3-celled inferior ovary, 

 one petal (the lip or labellum) usually complex in structure and differing only 

 slightly or greatly in form, size and coloration from the other segments; lip often 

 extended to form a spur or nectary; stamens and pistils (including the filaments 

 and styles) united to form an organ (the column) in the center of the flower; 

 column various, bearing at or near its summit or laterally 1 or 2 mobile or rigidly 

 attached anthers, producing in front on the ventral surface the somewhat con- 

 fluent stigmas, with one stigma usually modifled to form the rostellum; anthers 

 situated behind the rostellum, resting in a bed or clinandrium, perfectly or 

 abortively 2-celled, containing a mass of pollen or 2 to 8 distinct pollen masses 

 or pollinia; pollen powdery, granular-mealy, waxy or cartilaginous; fruit a dry 

 capsule or fleshy pod, commonly ovoid, ellipsoid or cylindrical, dehiscing along 1, 

 2 or 3 longitudinal sutures; seeds numerous, scobicular. 



A cosmopolitan family that attains its highest development in the tropics of 

 both hemispheres and is one of the largest families of flowering plants in the 

 world, consisting of several hundred genera and 15,000 or more species. It is also 

 considered to be among the most advanced families in the Monocotyledoneae. 

 The column, formed by the united stamens and pistils, is distinctive of the family. 



1. Flowers with a distinct saccate or elongated spur 1. Habenaria 



1. Flowers without a conspicuous spur, at most producing a short mentum (2) 



2(1 ). Lip broadly saccate or cymbiform; leaves rather large (3) 



2. Lip not saccate; leaves small, often grasslike (4) 



3(2). Leaves forming a basal rosette, shining and fleshy; lip uppermost in flower.. 

 7. Ponthieva 



3. Leaves scattered on the stem, plicate; lip lowermost in flower 3. Epipactis 



4(2). Lip crested or bearded on the face (5) 



4. Lip not crested or bearded on the face (7) 



5(4). Leaf linear to linear-lanceolate, grasslike, plicate, sheathing the scape near 

 the base; column broadly winged at the apex; lip forming the upper- 

 most segment of the perianth 6. Calopogon 



5. Leaf ovate to ovate-elliptic, fleshy; column not winged, clavate; lip forming the 



lowermost segment of the perianth (6) 



6(5). Lip 25 mm. long or less, bearded on the face 4. Pogonia 



6. Lip more than 30 mm. long, with a central crest 5. Cleistes 



7(4). Leaves several, basal or cauline, narrow and grasslike or (if broad) basal.. 

 8. Spiranthes 



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