THE COMMON WASP (continued)
Of the calamities that befall the Wasp when winter arrives, the worst
remains to be told. Foreseeing the approach of failing power, the
neuters, hitherto the tenderest of nurses, become savage exterminators:
“Let us leave no orphans,” they say to themselves; “no one would tend
them after we are gone. Let us kill everything, belated eggs and larvæ
alike. A violent end is preferable to slow death by starvation.”
A massacre of the innocents ensues. Seized by the scruff of the neck
and brutally extirpated from their cells, the larvæ are dragged out of
the nest and thrown into the vat at the bottom of the crypt; the eggs,
those delicate morsels, are ripped open and devoured. Will it be
possible for me to witness this tragic end of the city, not in the
fulness of its horror—that ambition is too far beyond my resources—but
at least in some of its scenes? Let us try.
In October, I place under cover a few fragments of a nest which have
been saved from asphyxiation. By moderating the dose of petrol I can
easily obtain a number of Wasps afflicted merely with a passing torpor,
which enables me to collect them without being stung and which
disappears as the sufferers are exposed to the air. Note also that,
even with a fairly strong dose of petrol, capable of killing all the
adults, the larvæ do not succumb. Mere digesting bellies, they hold out
when the more delicately-organized adults perish. Safe from
misadventure, I have been able in this way to establish in a cage a
portion of a nest rich in eggs and larvæ, with some hundred neuters as
attendants.
To facilitate my inspection, I separate the combs and place them side
by side, with the openings of the cells turned upwards. This
arrangement, which reverses the normal, does not appear to annoy my
captives, who, soon recovering from their disturbance, set to work as
if nothing unusual had occurred. In case they should wish to build, I
give them a slip of soft wood to draw upon. Lastly, I feed them with
honey, poured into a pool on a strip of paper and renewed daily. The
underground cavern is represented by a large earthen pan surmounted by
a wire-gauze cover. A cardboard dome, placed over the cover or removed
at will, provides alternately the obscurity demanded by the Wasps’
labours and the light needed for my observations.
The work is continued from one day to another. The Wasps attend at the
same time to the larvæ and to the house. The builders begin to erect a
wall round the most thickly-colonized combs. Do they intend to repair
the disaster and build a new envelope, which will replace the vanished
enclosing wall? The progress of the operation seems to tell us no. They
are simply continuing the work which my terrible flask and my spade
have interrupted. Over an area embracing hardly a third of the comb,
they erect an arched roof of paper scales which would have been joined
to the envelope of the nest had it been intact. They are not beginning
again; they are continuing.
In any case, the sort of tent thus obtained shelters but a small part
of the disk of cells. This is not for lack of materials. To begin with,
there is the slip of wood, providing, in my opinion, an excellent
supply of fibrous scraps. But the Wasps do not touch it. Perhaps I have
chosen the wrong sort of piece, being but ill-versed in the secrets of
Vespian paper-making.
To these raw materials, which are troublesome to work, they prefer the
old cells, now fallen into disuse. In these the felted fibres are ready
prepared and have only to be reduced to pulp again. With a slight
expenditure of saliva and a little grinding in the mandibles, it yields
a product of the highest quality. The uninhabited cells, therefore, are
demolished by degrees, nibbled and razed to their foundations. Out of
the ruins a sort of canopy is built. New cells would be constructed in
the same way if they were needed. This confirms what the upper stories
with demolished cells made us foresee: the Wasps build new cells with
old.
The feeding of the grubs deserves examination even more than this
roofing-work. One would never weary of the spectacle of these rough
fighters converted into tender nurses. The barracks are turned into a
crèche. What care, what vigilance in the rearing of the grubs! Let us
watch one of the busy Wasps. Her crop swollen with honey, she halts in
front of a cell; almost pensively she bends her head into the orifice;
she questions the recluse with the tip of her antenna. The larva wakes
and gapes at her, like the fledgeling when the mother-bird returns to
the nest with food.
For a moment, the awakened larva swings its head to and fro: it is
blind and is trying to feel the pap brought to it. The two mouths meet;
a drop of syrup passes from the nurse’s mouth to the nurseling’s. That
is enough for the moment. Now for the next. The Wasp moves on, to
continue her duties elsewhere.
The larva, on its side, licks the base of its neck for a few seconds.
There is here, at the moment when the grub is being served with food, a
sort of projecting bib, a temporary dewlap which forms a porringer and
receives what trickles from the lips. After swallowing the bulk of the
ration, the larva finishes its meal by gathering up the crumbs which
have fallen on its bib. Then the swelling disappears; and the grub,
withdrawing a little way into its cell, resumes its sweet slumbers.
The better to watch this curious fashion of eating, I happen by good
luck to have a few powerful Hornet-larvæ. I slip them singly into paper
sheaths, which will represent their natal cells. Thus swaddled, my fat
babies lend themselves excellently to observation when I myself
distribute their rations.
In my young days, we had a trick of tapping with our finger the
incipient tail of the Sparrow whom we were rearing. The pupil at once
yawned, ready to receive his food. I like to imagine that this system
of bird-training is still in vogue. But there is no need of these
stimulating preliminaries to arouse the appetite of the Hornet’s
offspring. They yawn of their own accord at the least touch that I give
to their cell. The lucky creatures have ever-ready stomachs.
Taking a piece of straw with a drop of honey hanging from it, I place
the delicious ration between the grub’s mandibles. There is too much
for a single mouthful. But the breast swells into a dewlap which
catches the surplus. Here the grub will take a few more sips, at its
leisure, after swallowing the spoonful which it received direct. When
there is no more left, when the pectoral platter is licked clean, the
swelling disappears and the larva resumes its immobility. Thanks to
this short-lived swelling, suddenly flung out and as suddenly
withdrawn, the diner has its table spread beneath its chin; without
assistance from others, it finishes its meal alone.
When fed in my cage, the Wasps’ grubs have their heads up; and what
escapes their lips collects upon the dewlap. When fed normally, in the
Wasps’-nest, they have their heads down. In this position is the
protuberance on the breast of any service? I cannot doubt it.
By slightly bending its head, the larva can always deposit on its
projecting bib a portion of the copious mouthful, which adheres to it
by reason of its stickiness. Further, there is nothing to tell us that
the nurse does not herself deposit the surplus of her helping on this
spot. Whether it be above or below the mouth, right way up or upside
down, the pectoral porringer fulfils its office because of the sticky
nature of the food. It is a temporary saucer which shortens the work of
serving and enables the grub to feed in a more or less leisurely
fashion and without too much gluttony.
In the cage my Wasps are fed with honey, which they disgorge for the
larvæ, once their crops are full. Both nurses and nurselings seem to
thrive on this diet. Nevertheless, I know that the usual food is game.
I have described elsewhere the hunting of the Eristalis by the Common
Wasp and of the Hive-bee by the Hornet. [67] The moment she is caught,
the big Fly in particular is dismembered; the head, wings, legs and
belly, those meagre portions, are cut off with snips of the shears.
There remains the breast, which is rich in muscular tissues. This is
the booty which, minced small upon the spot and reduced to a pill, is
carried to the nest as a feast for the larvæ.
To honey, therefore, let us add game. I slip a few Eristales under the
wire dome. At first the newcomers are not molested. The turbulent
Flies, fluttering, buzzing, butting their heads against the wire-gauze,
create no sensation in the cage. The inmates take no notice of them. If
one of them pass too near to a Wasp, the Wasp just raises her head, as
though in threat. That is quite enough; the Fly decamps.
Matters become more serious around the strip of paper covered with
honey. The refectory is assiduously frequented by the Wasps. If the
Eristalis, watching jealously from afar, venture to approach, one of
the banqueters separates from the group, rushes headlong at the daring
one, catches her by the leg and sends her to the right-about. The
encounter is not really grave except when the Fly commits the
imprudence of alighting on a comb. Then the Wasps fling themselves upon
the hapless intruder, roll her over and over, cuff her and drub her and
drag her outside crippled or, as often as not, dead. The body is
disdainfully rejected.
I renew my attempts in vain; I cannot reproduce the scenes which I used
to witness on the aster-blossoms: the capture of the Eristalis and her
reduction to mincemeat for the larvæ. Perhaps this strong animal fare
is distributed only on certain occasions which are not realized in my
cage; or perhaps—and I more incline to favour this idea—honey is judged
to be better than meat. My prisoners have plenty of it, served up fresh
daily. The nurselings thrive on this diet; and the salmis of Flies is
rejected in consequence.
But in the open country, in the late autumn, fruit is scarce; and, in
the absence of sweet pulp, we fall back upon game. Minced Eristalis may
well be only a secondary resource of the Wasps. Their refusal of my
offerings seems to prove it.
We will now consider the Polistes. Her absolutely Wasp-like shape and
costume take nobody in for a moment. She is at once recognized and is
mobbed as the Eristalis was, if she dare approach the honey whereat the
Wasps are sipping. On neither side, however, is there any attempt at
stinging: these table-quarrels are not worth the drawing of a dagger.
Realizing that she is the weaker and that she is not at home, the
Polistes retires. She will come back again and so persistently that the
diners end by allowing her to take her seat beside them, a concession
very rarely made to the Eristalis. This toleration does not last long:
if the Polistes but venture on the combs, this alone arouses a terrible
anger and brings about the death of the intruder. No, it is not a good
thing to enter the Wasps’-nest, even when the stranger wears the same
uniform, pursues the same industry and is almost a fellow-member of the
corporation.
Let us now try the Bumble-bee. Here is a male, quite a small one, clad
in russet. The poor little beggar is threatened and even hustled, but
no more, each time that he passes near a Wasp. Now, however, the
scatter-brain comes tumbling from the top of the trelliswork and drops
on a comb, in the midst of the busy nurses. I am all eyes as I follow
the tragedy. One of them seizes the Bumble-bee by the neck and stabs
him in the breast. A few convulsions of the legs follow; and the
Bumble-bee is dead. Two other Wasps come to the murderess’ assistance
and help her drag the deceased outside. Once more, I remark, it is not
a good thing to enter the Wasps’ nest, even by accident and without any
bad intention.
Here are a few more examples of the savage welcome given to strangers.
I do not select my victims; I use them as they happen to come. A
rose-tree outside my door supplies me with Hylotoma-larvæ, [68] larvæ
shaped like caterpillars. I place one in the midst of the Wasps, who
are busy with their cells. Great surprise on the part of the workers
confronted by this sort of green dragon, spotted with black! They come
near; they withdraw; they again come near. One snaps at it boldly,
inflicting a bleeding wound. Others follow her example, bite and
endeavour to haul away the wounded creature. The dragon resists,
holding now by its fore-legs and now by its hind-legs. The burden is
not too heavy, but the insect struggles indefatigably, anchored by its
hooks. However, after numerous attempts, the grub, enfeebled by its
wounds, is torn from the comb and dragged, all bleeding, to the
refuse-pit. It has taken a couple of hours to dislodge it.
With the Hylotoma-larva the Wasps did not use the sting, which would
have so promptly put an end to all resistance. Perhaps they deemed the
wretched grub unworthy of ceremonial death. The expeditious method of
the poisoned dagger appears to be reserved for great occasions. Thus
perished the Bumble-bee and the Polistes; thus will perish a larva of
the Scalary Saperda, [69] an imposing grub extracted that moment from
under the bark of a dead cherry-tree.
I fling it on one of the combs. The Wasps are greatly excited by the
fall of the monster, which goes into vigorous contortions. Five or six
at a time assail it, first quickly biting into it and then pricking it
with their stings. In a couple of minutes the grub, stabbed through and
through, no longer stirs. As for carrying the huge dead body out of the
nest, that is another matter; it is too heavy, much too heavy. What
will the Wasps do? Unable to shift the grub, they eat it where it lies,
or rather they drain it dry, drinking its blood. An hour later, flaccid
now and greatly diminished in weight, the cumbrous corpse is dragged
outside the walls.
The rest of my notes would only repeat the same results. If he keep a
certain distance, the stranger is tolerated, no matter what his race,
his costume or his habits. If he pass near a Wasp, a threat warns him
and puts him to flight. If he go to the pool of honey, when the
refectory is already occupied by the Wasps, it seldom happens that the
daring intruder is not molested and driven from the banquet. So far,
blows of no great gravity suffice. But, if he have the misfortune to
enter the actual nest, he comes to a bad end, pierced by the Wasps’
stings or at least disembowelled by the fangs of their mandibles. His
corpse goes to join the other refuse in the basement.
Protected with this fierce vigilance against the invasion of all
intruders and deliciously spoon-fed on honey, on that excellent honey
which causes Fly-meat to be forgotten, the larvæ prosper greatly in my
breeding-cage, though of course not all. In the Wasps’-nest, as
everywhere, there are weaklings who are cut down before their time.
I see these puny sufferers refuse their food and slowly pine away. The
nurses perceive it even more clearly. They bend their heads over the
sorely-tried grub, they sound it with their antennæ, they pronounce it
incurable. Then the creature at point of death, often of a sickly
brown, is torn ruthlessly from its cell and dragged outside the nest.
In the brutal commonwealth of the Wasps, the invalid is merely a clout,
to be got rid of as quickly as possible, for fear of contagion.
Woe to the sick among these rude professors of hygiene! Any and every
cripple is expelled and thrown to the maggot waiting to eat him in the
catacombs below. Should the experimenter intervene, matters take an
even more atrocious turn. I remove from their cells a few larvæ and
nymphs in excellent health and place them on the surface of the combs.
Once outside the cells, where the nymphs were maturing under a silken
cupola, while the larvæ were being spoon-fed with the utmost
tenderness, the delicate creatures are mere hateful obstacles and
useless encumbrances. Ferociously the workers tug at them, disembowel
them and even eat a little of them. After this cannibal repast, the
victims are carted outside the nest. Incapable of reentering their
cradles, even with assistance, larvæ and nymphs, stripped bare, perish,
slain by their nurses.
In the cage, however, the grubs generally display a well-fed, glossy
skin, a certificate of good health. But see what happens on the advent
of the first cold nights of November. The building proceeds with
diminished enthusiasm; the visits to the pool of honey are less
assiduous. Household duties are relaxed. Grubs gaping with hunger
receive tardy relief, or are even neglected. Profound uneasiness seizes
upon the nurses. Their former devotion is succeeded by indifference,
which soon turns to aversion. What is the use of continuing attentions
which presently will become impossible? In view of the imminent famine,
our beloved nurselings must die a tragic death.
The neuters, in fact, grab the late-born larvæ, these to-day, those
to-morrow, sooner or later the rest, and root them out of their cells
with the same violence which they would employ against a stranger or a
lifeless body; they tug at them, savagely rend them; and all this poor
flesh is sent down to the pit.
Before much longer, the neuters themselves, the executioners, are
languidly dragging what remains of their lives. At length they also
succumb, killed by the weather. November is not yet past; and nothing
is left alive in my cage. The final massacre of the tardy larvæ must
take place underground in more or less the same manner, but on a larger
scale.
Day after day the catacombs of the Wasps’-nest receive the dead and
dying hurled down from above, sickly larvæ and such Wasps as have been
injured by accident. Rare in the prosperous season, these falls into
the charnel-heap become increasingly frequent as winter approaches.
When the late-born grubs are being exterminated and above all at the
moment of the final catastrophe, when the adults, males, females and
neuters, are dying in their thousands, the manna descends in a copious
downfall daily.
The host of devourers has hastened up, receiving only a little at
first, but foreseeing great junketings in the future. By the end of
November, the bottom of the crypt is a swarming hostelry, dominated
numerically by the grubs of certain Flies, those undertakers of the
Wasps’-nests. I gather great numbers of the larvæ of the Volucella, who
deserves a chapter to herself, by reason of her fame. I find here,
poking its tapering head into the bellies of the corpses, a naked,
white, pointed maggot, smaller than that of the Luciliæ. [70] It works
promiscuously with a second, even smaller grub, brown and clad in a
prickly smock. I come upon a dwarf which, looping and unlooping,
wriggles about like the Cheese-mites.
All of them are dissecting, dismembering and disembowelling with so
much zeal that, when February arrives, they have not yet had time to
shrink into pupæ. It is so pleasant here, sheltered against the
inclemencies of the weather, in the snug basement, with provisions in
abundance! Why hurry? These smug eaters expect to consume the heap of
victuals before hardening their skin into a barrel. They linger so long
over their banquet that I forget to secure them for my rearing-phials;
and I can say no more about their history.
In the charnel-houses of Moles and Snakes in my aerial retting-vats,
[71] I used to note, from time to time, the arrival of the largest of
our Staphylini, [72] S. maxillosus, who, in passing, would make a brief
stay under the putrid mass and then proceed to pursue her business
elsewhere. The Wasps’ charnel-house similarly has short-winged Beetles
among its habitual visitors. I often come upon Quedius fulgidas, Fab.,
there, the one with the red wing-cases. But this time it is not a
temporary hostelry; it is a family establishment, for the adult
Staphylinus is accompanied by her larva. I also find Wood-lice and
Millipedes, of the genus Polydesma, both inferior trenchermen, feeding
probably on the humours oozing from the dead.
Let us also mention one of the outstanding insect-eaters, the tiniest
of our mammals, the Shrew, who is smaller than the Common Mouse. At the
time of the final catastrophe, when sickness has calmed the aggressive
fury of the Wasps, the visitor with the pointed muzzle steals into the
nest. Exploited by a pair of Shrew-mice, the dying crowd is soon
reduced to a heap of remnants which the maggots end by clearing out.
The ruins themselves will perish. A caterpillar that develops later
into a mean-looking, whitish Moth; a Cryptophagus, a tiny reddish
Beetle; and a larva of one of the Dermestes [73] (Attagenus pellio),
clad in scaly gold velvet, gnaw the floors of the stages and crumble
the whole dwelling. A few pinches of dust, a few shreds of brown paper
are all that remains, by the return of spring, of the Vespian city and
its thirty thousand inhabitants.