350 orchidejE. [Orchidea. 



attached in pairs to a stalk or caudicle, or all cohering by their points or 

 caudicles to a gland, detaching itself from the stigma. Ovary inferior, with 

 3 parietal placentas. Stigmas usually forming a hollow disk on the top of 

 the column, often with an erect projection in front of the anthers, called the 

 rostellum. Capsule 3-valved. Seeds innumerable, minute, resembling fine saw- 

 dust. Embryo a solid apparently homogeneous mass. — Herbs (rarely shrubs), 

 always perennial, either by means of a continuous stem or rhizome, or by an- 

 nually renewed tubers ; terrestrial or epiphytes j in the latter case the stems 

 or leaf-branches are often thickened at the base into false-bulbs. Leaves en- 

 tire, parallel- veined, usually sheathing at the base. Flowers usually in racemes 

 or spikes, sometimes solitary or panicled, with a bract under each flower. 



A large Order distributed over all parts of the globe, but most abundant within the 

 tropics. 



Tribe I. Operculatse. — Anther terminal and lid-like, not adnate, and usually decidu- 

 ous. Pollen-masses of a waxy consistence. Rhizome or base of the stem usually continu- 

 ously perennial, often producing false-bulbs, or the stems thickened at the base. Flowers 

 usually pedicellate. 



Racemes terminating the more or less leafy stem. 



Leaves 1 to 3 at or near the base of the flowering stem. 



Labellum inserted on a projection from the base of the column 



and forming with it a pouch or short spur 4. Eria. 



Labellum sessile at the base of the column. 



Sepals and petals very spreading. Flowers small. 



Column elongated. Labellum entire 1. Liparis. 



Column short. Labellum 3-toothed or lobed .... 2. Dienia. 

 Sepals and petals erect. 

 Anther-cells opening transversely in 2 valves .... 5. Pholidota. 



Anther-cells opening longitudinally 6. Ccelogtne. 



Leaves numerous, distant, distichous. 



Labellum convolute round the column. Flowers large. Leaves 



long and narrow . 7. Arundina. 



Labellum inserted on a projection from the base of the co- 

 lumn, and forming with it a spur or pouch. Flowers 



scarcely 4 lines. Leaves short 17. Appendicula. 



Racemes or flowers on leafless scapes proceeding from the rhizome 

 or creeping stem. 

 Labellum spurred at the base, convolute round the column . . 8. Phaius. 

 Labellum inserted on a projection from the base of the column, 

 and forming with it a short pouch. 

 Pollen-masses 2, fixed to glands at the base. Flowers large, 



yellow. Labellum large, concave 12. Cyrtopera. 



Pollen-masses 8, without glands. Sepals narrow. Labellum flat. 

 Scapes 1 ft. high or more, several-flowered. 



Sepals and petals scarcely spreading, pubescent. Raceme 



1-sided 10. Pachystoma. 



Sepals and petals very spreading, glabrous. Raceme loose 11. Ania. 

 Minute plant, with short filiform peduncles ...... 4. Eria. 



Labellum sessile at the base of the column, not saccate. 



Stems creeping and rooting. Peduncles at the base of 1- 



leaved false-bulbs 3. Bolbophyllum. 



Rhizome underground, shortly creeping or tuberous. No 

 false-bulbs. Leaves long. 

 Middle lobe of the labellum unguiculate ....... 9. Spathoglottis. 



Labellum entire or with a sessile middle-lobe . .. . . . 13. Cymbipium. 



