Thismia.] CXLVIL BURMANNIACEE. (J. D. Hooker.) 667 
Whole plant 3-4 in. high, very closely allied to T. Brunoniana, but differing in 
the solitary flower and orbicular perianth-lobes, 
Orpver CXLVIII. ORCHIDEZ. 
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 Cypripedieæ) 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 pyriform waxy or powdery masses (pollinia) which are 
ree or attached by pairs or fours to a viscus or gland, or a stalk (eaudicle) 
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 
40, species about 5000, temperate and tropical, rarely arctic. 
KEY TO THE TRIBES AND SUBTRIBES. 
TRIBE I. Bpidendres. -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 Cologynec the long bases of the pollinia 
resemble caudicles.) 
Subtribe 1. MaraxEx. Stems simple, leafy, rarely leafless, with often a 
Pseudobulbous base. Inflorescence terminal. Flowers small or minute. 
ther erect or inclined, usually persistent, not incumbent. Pollinia 4 
(or 8), subequal, close together, usually free (without a viscid appendage). 
Subtribe 2, Dexprosrem. Inflorescence terminal, lateral, or on a leafless 
"cape. Pollinia 4, rarely 2, Iseriate, parallel, appendage 0. 
8 Subtribe 3. Enrex. Inflorescence lateral, or on a leafless scape. Pollinia 
» Subequal, appendage 0 or obscure. 
Subtribe 4. Brgrrgx. Inflorescence usually lateral. Pollinia 8, except 
m Anthogonium, usually in 2 series, parallel, ascending, connected by a 
granular appendage. 
Subtribe 5. Orogywzx, Inflorescence terminal. Pollinia 8 or 4, sub- 
equal, connected by viscus or an appendage (in Calanthe and others, the 
n 1a are appendaged, but the appendage is an undeveloped portion of 
e pollen itself, and is not derived from the rostellum). 
