_Amphicarpa monoica (Falcata comosa)_
_Flowers_--Numerous small, showy ones, borne in drooping clusters from
axils of upper leaves; lilac, pale purplish, or rarely white,
butterfly-shaped, consisting of standard petal partly enfolding wings
and keel. Calyx tubular, 4 or 5 toothed; 10 stamens (9 and 1); 1 pistil.
(Also solitary fertile flowers, lacking petals, on thread-like, creeping
branches from lower axils or underground.) _Stem:_ Twining wiry
brownish-hairy, 1 to 8 ft. long. _Leaves:_ Compounded of 3 thin
leaflets, egg-shaped at base, acutely pointed at tip. _Fruit:_ Hairy pod
1 in. long. Also 1-seeded, pale, rounded, underground peanut.
_Preferred Habitat_--Moist thickets, shady roadsides.
_Flowering Season_--August-September.
_Distribution_--New Brunswick westward to Nebraska, south to Gulf
of Mexico.
_Amphicarpa_ (“seed at both ends”), the Greek name by which this
graceful vine is sometimes known, emphasizes its most interesting
feature, that, nevertheless, seems to many a foolish duplication of
energy on Nature’s part. Why should the same plant bear two kinds of
blossoms and seeds? Among the foliage of low shrubbery and plants in
shady lanes and woodside thickets, we see the delicate, drooping
clusters of lilac blossoms hanging where bees can readily discover them
and, in pilfering their sweets, transfer their pollen from flower to
flower. But in case of failure to intercross these blossoms that are
dependent upon insect help to set fertile seed, what then? Must the
plant run the risk of extinction? Self-fertilization may be an evil,
but failure to produce seed at all is surely the greatest one. To guard
against such a calamity, insignificant looking flowers that have no
petals to open for the enticing of insects, but which fertilize
themselves with their own pollen, produce abundant seed close to the
ground or under it. Then what need of the showy blossoms hanging in the
thicket above? Close inbreeding in the vegetable world, as in the
animal, ultimately produces degenerate offspring; and although the showy
lilac blossoms of the wild peanut yield comparatively few
cross-fertilized seeds, these are quite sufficient to enable the vine to
maintain those desired features which are the inheritance from ancestors
that struggled in their day and generation after perfection. No plant
dares depend upon its cleistogamous or blind flowers alone for
offspring; and in the sixty or more genera containing these curious
growths, that usually look like buds arrested in development, every
plant that bears them bears also showy flowers dependent upon
cross-pollination by insect aid.
The boy who:
“Drives home the cows from the pasture
Up through the long shady lane”
knows how reluctantly they leave the feast afforded by the wild peanut.
Hogs, rooting about in the moist soil where it grows, unearth the hairy
pods that should produce next year’s vines; hence the poor excuse for
branding a charming plant with a repellent folk-name.
This plant should not be confused with pig-nut (_carya porcina_), which
is a species of hickory.