distinct in habit as Hria microphylla, with leaves only 1 
cm. long, creeping over the bark of tropical trees, and the 
tall erect terrestrial savanna herbs of the genus Hudophia, 
as well as the saprophytes exemplified by phyllorchis, 
Corallorhiza, Didymoplexis, E:pipogium, Gastrodia and 
Neottia, which spend most of their lives hidden in sub- 
terranean darkness, can be held together in a single bo- 
tanical family, the Orchidaceae, only by emphasis on a 
common basic floral pattern by no means obvious to the 
uninitiated. The existence of such a ground plan of floral 
organization tends to be masked by fantastic variations 
upon it in size, shape and colour associated with pollina- 
tion mechanisms so complex as to be unbelievable were 
they not so well attested. Consequently, the concept of 
the Orchidaceae as a group of petaloid monocotyledons 
technically distinguished by such associated characters 
as a perigon of six segments zygomorphically developed, 
stamens reduced to one, two or three, ovary inferior and 
usually twisted (the whole flower then upside down) a 
stigma modified into a peculiar organ, the rostellum, 
seeds very numerous, minute and lacking endosperm— 
this concept has been long in the making. 
The orchids lack a single marked feature comparable 
to the umbel of Umbelliferae (Apiaceae), which led to the 
‘arly recognition of that aromatic economically impor- 
tant family. Nevertheless, they now present themselves 
to us as a natural group without conscious reference to 
their individual technical features. This recognition is 
the result of familiarity. The firm waxy texture of their 
flowers, in shape generally unlike those of other plants, 
their frequent use in floristry and their former association 
with wealth have established orchids as a generally known 
and popular group. They continually provide botanists 
with new problems and gardeners with new joys un- 
paralleled in any other botanical family. 
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