178 ORCHIDACEA. 
one (2 in Cypripediee), on the front or top or back of the column 
and free or adnate to it, 2-celled or by subdivision 4-celled; top of the- 
column sometimes produced towards the lip into a beak (rostellum) ;. 
pollen-grains usually coherent in each cell into 1, 2, or 4 pairs of 
oblong globose or pyriform waxy or powdery masses (pollinia), 
which are free or attached by pairs or fours immediately, or by ‘a 
stalk (caudicle) to a gland. Ovary inferior, 1-celled, usually linear 
or twisted ; stigma one or two viscid spots on the top or concave 
face of the column, opposite the lip and below the anther, rarely 
discoid and above the two anthers (in Cypripediee) ; ovules many, 
minute. Fruit a capsule, usually opening by 3 or 6 longitudinal 
fissures, rarely fleshy and subindehiscent. Seeds many, minute, 
with a lax hyaline testa enclosing a homogeneous nucleus.—Species: 
about 5,000, in temperate and tropical regions, rarely arctic. 
Anther single :— 
Pollinia waxy :— 
Polliria free, or those of each cell held 
together at the base by a viscid ap- 
pendage, not attached by their bases or 
by a caudicle to the rostellum :— 
Pollinia 4 :— 
Leaves equitant, -oriaceous or fleshy. 
Epiphytic her » . : 1. OBERONIA. 
Leaves not equ cant. Usually ter- 
restrial herbs — 
Leaves membranous, rarely coriace- 
ous :— 
Lip suy rior, with basal auricles ; 
column very short - . 2. MicrosTy.is. 
Lip inferior, without basal 
auricles; columnlong . i. ae er ARES. 
Epiphytic herbs with coriaceous 
leaves :— 
Stems solitary or cespitose, or 
composed of discrete pseudo- 
bulbs basally attached on a 
Jong or short rhizome ; column 
prolonged into a foot :— 
Lip not articulate on the foot 
ofthe column . : . 4. DENDROBIUM. 
