_Habenaria fimbriata (H. grandiflora)_
_Flowers_--Pink-purple and pale lilac, sometimes nearly white; fragrant,
alternate, clustered in thick, dense spikes from 3 to 15 in. long. Upper
sepal and toothed petals erect; the lip of deepest shade, 1/2 in. long,
fan-shaped, 3-parted, fringed half its length, and prolonged at base
into slender, long spur; stamen united with style into short column; 2
anther sacs slightly divergent, the hollow between them glutinous,
stigmatic. _Stem:_ 1 to 5 ft. high, angled, twisted. _Leaves:_ Oval,
large, sheathing the stem below; smaller, lance-shaped ones higher up
bracts above. _Root:_ Thick, fibrous.
_Preferred Habitat_--Rich, moist meadows, muddy places, woods.
_Flowering Season_--June-August.
_Distribution_--New Brunswick to Ontario; southward to North Carolina,
westward to Michigan.
Because of the singular and exquisitely unerring adaptations of orchids
as a family to their insect visitors, no group of plants has greater
interest for the botanist since Darwin interpreted their marvellous
mechanism, and Gray, his instant disciple, revealed the hidden purposes
of our native American species, no less wonderfully constructed than the
most costly exotic in a millionaire’s hothouse.
A glance at the spur of this orchid, one of the handsomest and most
striking of its clan, and the heavy perfume of the flower, would seem to
indicate that only a moth with a long proboscis could reach the nectar
secreted at the base of the thread-like passage. Butterflies, attracted
by the conspicuous color, sometimes hover about the showy spikes of
bloom, but it is probable that, to secure a sip, all but possibly the
very largest of them must go to the smaller Purple-fringed Orchis, whose
shorter spur holds out a certain prospect of reward; for, in these two
cases, as in so many others, the flower’s welcome for an insect is in
exact proportion to the length of its visitor’s tongue. Doubtless it is
one of the smaller sphinx moths, such as we see at dusk working about
the evening primrose and other flowers deep of chalice, and heavily
perfumed to guide visitors to their feast, that is the great
Purple-fringed Orchid’s benefactor, since the length of its tongue is
perfectly adapted to its needs. Attracted by the showy, broad lower
petal, his wings ever in rapid motion, the moth proceeds to unroll his
proboscis and drain the cup that is frequently an inch and a half deep.
Thrusting in his head, either one or both of his large, projecting eyes
are pressed against the sticky button-shaped discs to which the pollen
masses are attached by a stalk, and as he raises his head to depart,
feeling that he is caught, he gives a little jerk that detaches them,
and away he flies with these still fastened to his eyes.
Even while he is flying to another flower, that is to say, in half a
minute, the stalks of the pollen masses bend downward from the
perpendicular and slightly toward the centre, or just far enough to
require the moth, in thrusting his proboscis into the nectary, to strike
the glutinous, sticky stigma. Now, withdrawing his head, either or both
of the golden clubs he brought in with him will be left on the precise
spot where they will fertilize the flower. Sometimes, but rarely, we
catch a butterfly or moth from the smaller or larger purple orchids with
a pollen mass attached to his tongue, instead of to his eyes; this is
when he does not make his entrance from the exact centre--as in these
flowers he is not obliged to do--and in order to reach the nectary his
tongue necessarily brushes against one of the sticky anther sacs. The
performance may be successfully imitated by thrusting some blunt point
about the size of a moth’s head, a dull pencil or a knitting-needle,
into the flower as an insect would enter. Withdraw the pencil, and one
or both of the pollen masses will be found sticking to it, and already
automatically changing their attitude. In the case of the large,
round-leaved orchis, whose greenish-white flowers are fertilized in a
similar manner by the sphinx moth, the anther sacs converge, like little
horns; and their change of attitude while they are being carried to
fertilize another flower is quite as exquisitely exact.