te, it would seem, in the popular mind.
Of over 3000 known species of orchids, it is true a great majority are
air-plants, or epiphytes--growing upon trees and other plants, obtaining
their sustenance from the air, and not truly parasitic; but of the
fifty-odd native species of the northeastern United States, not one is
of this character, all growing in the ground, like other plants. It is
only by the botanical structure of the flowers that the orchid may be
readily distinguished, the epiphytic character being of little
significance botanically.

A brief glance at this structural peculiarity may properly precede our
more elaborate consideration of a few species of these remarkable
flowers.

The orchids are usually very irregular, and six-parted. The ovary is
one-celled, and becomes a pod containing an enormous yield of minute,
almost spore-like, seeds (Fig. 3) in some species, as in the vanilla
pod, to the number of a million, and in one species of the maxillaria,
as has been carefully computed, 1,750,000.

The pollen, unlike ordinary flowers, is gathered together in waxy masses
of varying consistency, variously formed and disposed in the blossom,
its grains being connected with elastic cobwebby threads, which
occasionally permit the entire mass to be stretched to four or five
times its length, and recover its original shape when released. This is
noticeable specially in the _O. spectabilis_, later described. The
grains thus united are readily disentangled from their mass when brought
into contact with a viscid object, as, for instance, the stigma.

[Illustration: Fig. 1]

But the most significant botanical contrast and distinction is found in
the union of the style and stamens in one organ, called the column (Fig.
2), the stigma and the pollen being thus disposed upon a single common
stalk. The contrast to the ordinary flower will be readily appreciated
by comparison of the accompanying diagrams (Fig. 1).

When, therefore, we find a blossom with the anthers or pollen
receptacle united to a stalk upon which the stigma is also placed, we
have an orchid.

The order is further remarkable, as Darwin first demonstrated in his
wonderful volume "The Fertilization of Orchids," in that the entire
group, with very few exceptions, are absolutely dependent upon insects
for their perpetuation through seed. They possess no possible resource
for self-fertilization in the neglect of these insect sponsors.

[Illustration: Fig.