CXXXIII. ORCHIDE^ (rOLFE). 13 



So-called disc or central part usually bearing crests or appendages, and 

 the base sometimes extended into a sac or spur. Stamens and style 

 united into a central column which faces the lip. Anther (in the 

 African genera) solitary, on the top or back of the column, and more 

 or less adnate to it, 2- or 4-celled. Pollen-grains cohering in 2-8 

 globose or club-shaped, waxy or granular masses, called pollinia, which 

 are free or cohere in pairs or fours or altogether by a viscid append- 

 age, and sometimes attached to a distinct stipes and gland. Ovary 

 inferior, 1 -celled with parietal placentas in the African genera, undeve- 

 loped at flowering-time. Stigma either consisting of a viscid surface 

 near the top of the concave side of the column or two-lobed and lateral ; 

 in the former case it faces the lip, and is usually separated from the 

 anther, below which it lies, by an appendage called the rostellum. 

 Seeds very numerous, minute, fusiform ; testa loose, reticulated, enclos- 

 ing a homogeneous embryo. — Herbs of various habit, or rarely 

 shrubby ; in many cases terrestrial, with tuberous roots or perennial 

 creeping rhizomes, annual herbaceous stems and solitary spicate or 

 racemose flowers, or in other cases epiphytal, with perennial stems 

 or branches, variously thickened and forming pseudobulbs, upon which 

 the leaves and flowers are borne, or the latter sometimes produced 

 below them. Leaves alternate, simple, entire, coriaceous or mem- 

 branous. Inflorescence terminal, basal or axillary, spicate, racemose 

 or paniculate, sometimes single-flowered. 



The largest order among monocotyledons, the species now known being estimated 

 at over five thousand. They are found throughout the globe, except in the highest 

 latitudes and altitudes, and the more remote oceanic islands. The epiphytic species 

 are for the most part confined to the intertropical zone, within which they are most 

 numerous in the mountains of Tropical Asia and America; in Tropical Africa, 

 however, the majority of the species are terrestrial. 

 Pollinia waxy. 



Anther 2.celled ; pollinia 2-8, united by a viscid 



appendage, free from the rostellum . . Tribe 1. EPIDENDRE^. 



Pollinia 4, sometimes cohering in pairs. 



Column not produced into a foot at the base ; 

 lip continuous with the base of the column; 



flowers with spreading perianth segments Subtribe i. MALAiEiE. 

 Column produced into a foot at the base ; lip 

 articulated to the foot of the column; 

 flowers with erect or subconnivent peri- 

 anth segments ..... Subtribe ii. Dendrobie^. 

 Pollinia 8. 



Column produced into a very short foot at the 

 base ; lip attached to the foot of the 



column ; subsaccate at the base . . Subtribe iii. Erie^. 



Column footless ; lip inserted at the base of 

 the column, and either convolute round 

 it or more or less adnate to it ; its base 



produced into a slender spur . . Subtribe iv. BLETiEiB. 



Anther cells usually confluent ; pollinia 2 or 4, 

 attached singly or in pairs to a stipes and 

 gland (a process of the rostellum), with which 

 they are carried away upon removal . . Tribe 2. VANDEiE. 



