178 



OECHIDACEM. 



one (2 in Cypripediece), 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) j, 

 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 Cypripediece) ; ovules many, 

 minute. Fruit a capsule, usually opening by 3 or 6 longitudinal 

 fissures, rarely fleshy and subinclehiscent. 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 : 

 Polliuia waxy : 



Pollinia 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, xuiaceous or fleshy. 



Epiphytic her * . . . .1. OBERONIA. 

 Leaves not eq j cant. Usually ter- 

 restrial herbs 



Leaves membranous, rarely coriace- 

 ous : 

 Lip sup .f ior, with basal auricles ; 



column very short . .2. MICROSTYLIS* 



Lip inferior, without basal 



auricles ; column long . . 3,. LIPABIS. 



Epiphytic herbs with coriaceous 

 leaves : 



Stems solitary or cssspitose, or 

 composed of discrete pseudo- 

 bulbs basally attached on a 

 Jong or short rhizome ; column 

 prolonged into a foot : 

 Tap not articulate on the foot 



of the column . . .4. DENDROBIUM*. 



