Thismia.] CXLVII. BURMANNIACE^E. (J. D. Hooker.) 667 



Whole plant 3-1 in. high, very closely allied to T. Urunoniana, but differing in 

 the solitary flower and orbicular perianth-lobes. 



ORDER CXLYIII. ORCHXDZUE. 



Herbs of various habit, rarely shrubby, of two principal forms : 1, 

 terrestrial, tuberous-rooted herbs, with annual herbaceous simple stems 

 and solitary or spicate or racemose flowers ; 2, epiphytes with perennial 

 stems or branches variously thickened and forming a pseudobulb, flowering 

 from the top sides.or base*of the pseudobulb. Perianth superior, irregular, of 

 6 free or variously combined pieces ; 3 outer (sepals) more or less alike, the 2 

 lateral sometimes united into a short or long sac or spur-like base (mentum) ; 



, 3 inner (petals) dissimilar,, the 2 lateral alike, the other (lip) usually very 

 differently shaped. Stamens and style united in a column opposite the lip, 

 anther (except in Cypripediece) solitary on the front or top or back of the 

 column and free or adnate to it, 2-celled or by subdivisions- 4-celled ; top of 

 the column sometimes produced in front (towards the lip) into a beak 

 (rostellum) ; pollen grains usually cohering in each cell into 1, 2, or 4 pairs 



- of oblong globose or pyriforin waxy or powdery masses (pollinia) which are 

 free or attached by pairs or fours to a viscus or gland, or a stalk (caudicle) 

 that terminates in a gland and by which the pollen mass or masses may be 

 removed entire. Ovary inferior, 1-celled (3-celled in Apostasia), usually 

 linear and twisted ; stigma a viscid surface on the top or concave face of 

 the column, opposite the lip and below the anther (in Cypripedium the 

 anthers are 2, one on each side of the base of a short style with a discoid 

 stigma). Seeds minute, testa lax enclosing a homogeneous nucleus. Genera 

 340, species about 5000, temperate and tropical, rarely arctic. 



KEY TO THE TRIBES AND SUBTRIBES. 



TRIBE I. Epidendreae. -Anther 1, opercular, usually deciduous, 

 cells parallel, distinct. Pollinia waxy, 1-4 in each cell, free, or those of 

 each cell held together at the base by a viscid appendage, not attached by 

 their bases or by a caudicle to the rostellum. (5 Tipularia has caudicled 

 pollinia, and in Calanthe and other Cmlogynece the long bases of the pollinia 

 resemble caudicles.) 



Subtribe 1. MALAXED. Stems simple, leafy, rarely leafless, with often a 

 pseudobulbous base. Inflorescence terminal. Flowers small or minute. 

 Anther erect or inclined, usually persistent, not incumbent. Pollinia 4 

 (or 8), subequal, close together, usually free (without a viscid appendage). 



Subtribe 2. DENDROBIE^E. Inflorescence terminal, lateral, or on a leafless 

 scape. Pollinia 4, rarely 2, 1 seriate, parallel, appendage 0. 



Subtribe 3. ERIE.E. Inflorescence lateral, or on a leafless scape. Pollinia 

 8, subequal, appendage or obscure. 



Subtribe 4. BLETIE^E. Inflorescence usually lateral. Pollinia 8, except 

 in Anthogonium, usually in 2 series, parallel, ascending, connected by a 

 granular appendage. 



Subtribe 5. CCELOGYNE&. Inflorescence terminal. Pollinia 8 or 4, sub- 

 equal, connected by viscus or an appendage (in Calanthe and others, the 

 pollinia are appendaged, but the appendage is an undeveloped portion of 

 the pollen itself, and is not derived from the rostellum). 



