PELOPÆUS CÆMENTARIUS. Abdomine petiolato nigro, segmento primo (excl.
pedunc.) lunulâ flavâ thoraceque punctis flavis, pedibus flavis
posticorum femoribus apiceque tibiarum nigris. (Long. Corp. 1 unc.)
SYN. Sphex Cæmentaria, _Drury, App. vol._ 2.
Pelopæus lunatus, _Fabr. Syst. Piez._ 203.
HABITAT: Jamaica, Antigua, St. Christopher's (_Drury_). "In America
insulis, in India orientali frequens." (_Fabricius_, incorrectly?)
Head black and hairy. Antennæ black, basal joint yellow. Thorax black,
with short hairs on it, but next the head yellow, having a yellow spot at
the base of each wing, and another next the abdomen. Wings brown, and
almost transparent; lying flat, not folded. Abdomen black and round,
nearly as long as the thorax; basal segment (exclusive of the peduncle)
yellow; pointed at the tip, and armed with a retractile sting. Peduncle
very slender, black at top, and yellow underneath; being nearly the
length of the thorax itself. Breast black. Fore and middle legs black
next the body, but from the middle of the thighs yellow. Hinder thighs
and lower parts of the shins black, the remainder yellow. Claws black.
The following particulars relative to the economy of this species were
communicated to Mr. Drury from a correspondent in Antigua, who forwarded to
him specimens of the insect.
"This insect is called at Antigua, and several other places in the West
Indies, the Mason Fly, a name given it from the remarkable manner in which
it builds its nest, or receptacle for its young.
"When the male and female have performed the business of copulation,
their[30] next care is to provide a proper habitation for raising and
securing their future progeny; to this end they seek out a proper spot that
is secure from rains, &c. and is so situated as to afford a {100}sufficient
warmth for the young offspring, but not so hot as to destroy instead of
nourishing them. The sides of a wall underneath the eaves of a house, is
the place often pitched on for this purpose. Thus prompted by nature, and
instinctively knowing the necessity of performing this work, they carry a
quantity of dirt, and place it against the wall, which they temper and
soften with a liquor issuing from their bodies, that renders it
sufficiently strong and tenacious, and when dry, is proof against any rains
that may happen to get at it. The nest is composed generally of about a
dozen cells, that are round, and sufficiently capacious to hold the
caterpillar when grown to its full size; each of which is about an inch
long, and about three-eighths of an inch in diameter, lying parallel with
each other, and formed in such a manner, that each cell lies between two
others, both above and below it, except the outward ones, having a hole
left open at the extremity of each, for the parents to go in and out at
pleasure. See Plate 45. Fig. 8. that at 9 being a nest supposed to be cut
through its middle, to shew the form of the cells, and manner of their
being built. The industry exerted on this occasion is remarkably great, for
in a few days the whole is completed. There is no doubt but the heat of the
climate greatly contributes to facilitate this work, as the dirt of which
it is composed is quickly dried, and by that means enables them to be very
expeditious. Their next employment is procuring a number of small spiders,
with which each cell is properly filled, and are to serve for food to the
young brood; of these they always take care to lay in such a sufficient
store, that the young ones seldom, if ever, perish from want. I have opened
many of these cells, and constantly found a spider remaining uneat,
sometimes two, and not seldom three, so that it is evident the parent
animal makes ample provision for the appetite of its young. By the time one
cell is replenished with provision, the pregnant female, finding the eggs
within her ripening to maturity, and under the necessity of discharging
them, lays a single one in the cell, and then covers up the hole with dirt,
which was left open for a passage, in so neat and curious a manner, that
the nicest eye could not discover the place where they used to enter. She
then proceeds in the same manner to the next, and so on, till all her eggs
are emitted and laid in their respective cells, each cell being furnished
with a single egg and no more. My correspondent assures me, he is not
certain whether the male assists in building the nest, or whether it is the
sole production of the female; but they both equally contribute to furnish
it with provision, which they carefully watch and preserve from the ants,
that in that hot climate would soon rob them of. In a little time the young
ones are hatched; and each, finding in its respective habitation a proper
quantity of food, subsists thereon, and there lives unseen, till it arrives
to its complete state. When it (the caterpillar) is advanced to its full
size, it forms round itself a brown case, as appears at Fig. 7. Plate 44.
and at Fig. 10. Plate 45. and in that inclosure undergoes its
transformation; when it puts on its form as at Fig. 8. Plate 44. remaining
with its legs, wings, and horns, closed round, as is there shewn, till it
has acquired strength to break its enclosure. At its first assuming this
form, it is white, soft, and tender, and its wings shorter than those in
the figure; in a few weeks its becomes hard, strong, and of its proper
{101}colour. The wings, also, before that time, grow to their proper size;
and now, finding itself arrived at a period when the forementioned
circumstance of its confinement is no longer necessary to its well being,
it obtains its liberty, by making a hole at the end of its cell, with its
jaws and fore legs, large enough to permit its escape.
"The separation of the thorax and abdomen, by such a long slender membrane
or ligament, is very singular, and the power the insect is invested with,
by means of those jaws or forceps placed at its mouth, is really wonderful;
for the number of insects, of a superior strength, as well as size, which
it is capable of destroying, is scarcely credible. It will overcome a
spider of twice its own size, if it can but get upon the back of it, by
means of its forceps and sting: nor will multitudes of other insects find
it a less formidable enemy, if they are not guarded by nature with a
covering too hard to yield to the force of these destructive weapons. In
short, it seems to be an animal formed by nature, as one of those
instruments instituted for subduing and lessening the vast numbers of small
insects that abound in warm climates."