GENUS. OPHION, _Fabr._ Ichneumon, _Drury_.
OPHION MACRURUM. Fusco-luteum; alis hyalinis, abdomine thorace triplo
longiori ensato. (Long. Corp. 1 unc. 3 lin.)
SYN. Ichneumon Macrurus, _Linn. Mant. p._ 540. _Drury, Append, vol._ 2.
HABITAT: New York.
{93}Head small, dark orange-coloured. Eyes large, black, and oblong.
Ocelli shining brown. Antennæ nearly the length of the insect, brown
orange, and resembling threads. All the other parts of the insect are of
the same brown orange, except the wings, which are transparent. Thorax
short. Abdomen three times as long as the thorax, very small at the base,
like a thread, but increasing in depth (not in thickness) to the
extremity, where it appears square and even as if obliquely cut off;
arched from the base to the tip. Legs slender, the hinder ones being the
longest. Tips of the tibiæ with two long spines, those of the fore legs
having only one.
This insect very closely resembles the common English species Ichneumon
luteus, Linn. It is, however, considerably larger.
After describing this insect our author took occasion to enter into the
natural history of the family to which it belongs, namely, the
Ichneumonidæ, so named from the Linnæan genus Ichneumon, which last he
says, "appears to be taken from its nature and way of life." He then
proceeds as follows:--
"It is generally known that butterflies are produced from caterpillars, and
that these caterpillars put on different forms before they arrive to that
of the butterfly; but few persons know, who have not engaged in this study,
that the bodies of these caterpillars are receptacles or habitations for
lesser insects, that live and grow within them during a certain time; where
they are nourished and fed by the juices of their bowels, till they arrive
to a mature age; when, by the appointment of nature, they kill their
fosterers, being totally unable to live on any other kind of food but what
the intestines of these animals supply them with. The uses and advantages
accruing to mankind by the institution of such a genus of insects, together
with their natural history, are the subject of the following lines.
"If we examine the glorious works of the creation, and reflect on the
paternal care and wisdom of the Almighty, displayed in the preservation and
increase of all ranks and kinds of animals; that even the most direful and
noxious, have such a proportion in the scale of life, as is most agreeable
to the ends of His divine providence; that the limits He hath prescribed to
each, extend so far and no farther; and that each species shall multiply in
such abundance or scarcity, as are best adapted to preserve, by a just
equilibrium, the harmony of the universe: When, I say, we behold this, the
mind can scarcely forbear crying out, under a rapturous sense of
conviction, "every thing is good." It is to this end we see the strong are
permitted to prey on the weak; and that the number of the latter increase
in a proportion sufficient to supply the wants of the former; it is to this
end we see some feed on herbs and plants, some on fruits and seeds, and
some on flesh; each being furnished with appetites and powers, suited to
their respective ways of life: and it is to this end, we see those of the
most minute kinds, abounding in a degree far beyond those of the first
magnitude. The knowledge of the insect kingdom illustrates this observation
beyond all possibility of doubt; and the number that may be bred from a
single pair, in many species, would exceed all credibility, if it was not
to be proved by any person who {94}would take the trouble. The wonderful
increase that only two summers would be capable of producing among many of
them, if each egg was to yield its respective insect, is amazing. The world
itself, in a few years, would be incapable of affording plants sufficient
for the nourishment of one single species.[29]
"Hence will appear the 'loving kindness' of the Almighty, in setting such
bounds, and keeping them within such limits as best answers the purpose for
which He created them; and hence appears the necessity of their becoming
food to other animals. Birds, fishes, and the smaller kinds of beasts, are
at eternal war with them; but as all these would be insufficient of
themselves to restrain and prevent them from multiplying too fast, other
kinds of beings are instituted for this end, whose existence depends on
their destruction. Of these, the species of insect I am describing, is the
most singular, of which (genus) there are several sorts, differing greatly
in size and shape. Some are furnished with three setæ or bristles at the
extremity of their bodies, the middle one being a hollow tube, secured or
fenced by the outer ones, through which they eject their eggs, after they
have penetrated the body of the caterpillar they settle on. Some appear to
have no bristles, others have them bent close under their bodies, and are
not to be seen, unless closely examined. As their whole business appears to
be the destroying the caterpillars of the butterfly and moth tribes, they
are indefatigable in the pursuit of them; but as this is confined to the
pregnant females, they are observed ranging about continually in search of
the proper subjects to lay their eggs on; flying on every bush, and running
with unwearied diligence on every twig, till they have arrived to the place
where the scent of the caterpillar soon furnishes them with the certainty
of its being there. Having thus discovered the animal it was in quest of,
the Ichneumon immediately settles on it, with an intent to discharge its
eggs; but the caterpillar being sensible, from a natural instinct, of its
enemy's assault, bends its head backwards to the place where it feels
itself attacked, and endeavours by various means, either by striking its
head violently against the part, falling to the ground, or by some sudden
contortion, to disengage itself: but this seldom happens, unless the
Ichneumon is feeble, and unable to withstand the shocks of the caterpillar;
in which case they will frequently relinquish their attack, and seek out
some other subject, whose resistance they are more capable of encountering.
On the other hand, if the Ichneumon is strong enough to withstand the
efforts of the caterpillar, it either lays its eggs on the outside of the
skin, as is the nature of some to do, or else perforates the body with the
bristle before described, and immediately discharges an egg. Some of these
Ichneumons quit the caterpillar upon the emission of an egg, but others
{95}continue thereon till they have emitted them all; which sometimes is
more than an hundred. It is necessary to observe, that many caterpillars of
moths and butterflies (the former more especially) are infested by a
particular species of these Ichneumons, that confine themselves entirely to
them alone, and never, that we know of, attack any other. Thus that of the
Privet Hawk or Sphinx Ligustri of Linnæus, that of the Elephant Hawk or
Sphinx Elpenor of the same author, &c. are always found to yield particular
kinds of Ichneumons. Others, indeed, attack any kind of caterpillar
belonging to the farinaceous-winged tribe; and, as I observed above, if not
too powerful and strong for them, will there deposit their eggs.
"If the egg is laid on the body of the caterpillar, and not within it, a
few days, by the warmth of the sun, ripens it to maturity; and then the
young destroyer, directed by nature, eats its passage through the
under-side of the egg, and passes into the body of the caterpillar, but if
the egg is discharged into its body, it there ripens, unseen, to maturity.
In either case, it lives on the substance or juices of its intestines;
thriving and increasing in bulk, in a proportion equal to the creature it
is doomed to kill. The caterpillar, also, notwithstanding its having thus
received the means of a slow but certain death, increases in size, and, to
outward appearance, in health; arriving to the period when it is to undergo
its metamorphosis, and become a Chrysalis, in as much strength and vigour
as any other of the species: but when the time arrives for its enlargement
into its complete state, and to become a moth or butterfly, the Ichneumon
makes its appearance; having arrived to its time of completion within the
body of its supporter, and exhausted its juices by the nourishment drawn
from it, leaving behind it a dry empty shell, in the form of a chrysalis.
"In this manner many of these Ichneumons exist. Others, when arrived to
maturity, having lived within the bodies of the caterpillars, as described,
eat their way out through its sides, and, crawling to a small distance,
form round themselves cases of a substance like silk; wherein, having lain
a few days, they quit their prisons in the shape of very small flies, some
having two wings, others four."--Vide Goedartius, Albin, Wilks, Harris, &c.