64 FAMILIES OF FLOWERING PLANTS. 
that of the ovary, or, as it is more generally expressed, the ovary is 
inferior. ‘The stamens are three or six, and the style is either simple 
or 8-cleft. In the South they may 
be found in rich woods, growing 
{in moist decaying vegetable mat- 
ter, Owing to the absence of 
leaves it was for a long time sup- 
posed that these plants were root- 
parasites like the broom-rapes. 
Figure 53 shows Burmannia bi- 
flora and Apteria sctacea of natur- 
al size; the former is distinguished 
by having flowers with the peri- 
-anth conspicuously wing-mar- 
gined. 
ef, Family Orchidaceae. Orchid 
Qa 2 Family. This large and most at~ 
Fic. 58a, Burmannia biflora. b. Apteria tractive group includes the most 
» Setaced. Plants natural size. Original. highly specialized of the monoco- 
tyledonous plants. The carefully 
conducted researches of Darwin and other scientists have demonstrated 
that the marvelous complexity of floral structure exhibited by the: 
orchids is the result of special adap- 
tation or modification to secure fer- 
tilization through insect agency, and 
often through the visits of some par- 
ticular species of insect. 
- Orchids are perennial herbs, 
with great diversity of habit. It 
may be stated as a general rule that 
those growing in temperate climates 
are terrestrial like most other plants, 
while those that are natives of warm 
or tropical regions are epiphytic, 
like the Bromeliads which were dis- . 
cussed in a recent chapter (see sup- 
plement, page 41). The roots of ter- 
restrial species are usually thickened 
and tuberous, sometimes even bul- 
showing parts of flower. (After Britton 
and Brown, Ill. Fl. Northeastern U.S. | 
