The Melecta does what she can with the gifts at her disposal. I should
leave it at that, if I had not to take into consideration a grave charge
brought against her. She is accused of having lost, for want of use and
through laziness, the workman's tools with which, so we are told, she
was originally endowed. Finding it to her advantage to do nothing,
bringing up her family free of expense, to the detriment of others, she
is alleged to have gradually inspired her race with an abhorrence for
work. The harvesting-tools, less and less often employed, dwindled
and perished as organs having no function; the species changed into
a different one; and finally idleness turned the honest worker of the
outset into a parasite. This brings us to a very simple and seductive
theory of parasitism, worthy to be discussed with all respect. Let us
set it forth.
Some mother, nearing the end of her labours and in a hurry to lay her
eggs, found, let us suppose, some convenient cells provisioned by her
fellows. There was no time for nest-building and foraging; if she would
save her family, she must perforce appropriate the fruit of another's
toil. Thus relieved of the tedium and fatigue of work, freed of every
care but that of laying eggs, she left a progeny which duly inherited
the maternal slothfulness and handed this down in its turn, in a more
and more accentuated form, as generation followed on generation; for the
struggle for life made this expeditious way of establishing yourself one
of the most favourable conditions for the success of the offspring. At
the same time, the organs of work, left unemployed, became atrophied and
disappeared, while certain details of shape and colouring were modified
more or less, so as to adapt themselves to the new circumstances. Thus
the parasitic race was definitely established.
This race, however, was not too greatly transformed for us to be able,
in certain cases, to trace its origin. The parasite has retained more
than one feature of those industrious ancestors. So, for instance,
the Psithyrus is extremely like the Bumble-bee, whose parasite and
descendant she is. The Stelis preserves the ancestral characteristics of
the Anthidium; the Coelioxys-bee recalls the Leaf-cutter.
Thus speak the evolutionists, with a wealth of evidence derived not only
from correspondence in general appearance, but also from similarity in
the most minute particulars. Nothing is small: I am as much convinced of
that as any man; and I admire the extraordinary precision of the details
furnished as a basis for the theory. But am I convinced? Rightly or
wrongly, my turn of mind does not hold minutiae of structure in great
favour: a joint of the palpi leaves me rather cold; a tuft of bristles
does not appear to me an unanswerable argument. I prefer to question the
creature direct and to let it describe its passions, its mode of life,
its aptitudes. Having heard its evidence, we shall see what becomes of
the theory of parasitism.
Before calling upon it to speak, why should I not say what I have on my
mind? And mark me, first of all, I do not like that laziness which is
said to favour the animal's prosperity. I have also believed and I still
persist in believing that activity alone strengthens the present and
ensures the future both of animals and men. To act is to live; to work
is to go forward. The energy of a race is measured by the aggregate of
its action.
No, I do not like it at all, this idleness so much commended of science.
We have quite enough of these zoological brutalities: man, the son of
the Ape; duty, a foolish prejudice; conscience, a lure for the simple;
genius, neurosis; patriotism, jingo heroics; the soul, a product of
protoplasmic energies; God, a puerile myth. Let us raise the war-whoop
and go out for scalps; we are here only to devour one another; the
summum bonum is the Chicago packer's dollar-chest! Enough, quite enough
of that, without having transformism next to break down the sacred law
of work. I will not hold it responsible for our moral ruin; it has not
a sturdy enough shoulder to effect such a breach; but still it has done
its worst.
No, once more, I do not like those brutalities which, denying all that
gives some dignity to our wretched life, stifle our horizon under an
extinguisher of matter. Oh, don't come and forbid me to think, though it
were but a dream, of a responsible human personality, of conscience, of
duty, of the dignity of labour! Everything is linked together: if the
animal is better off, as regards both itself and its race, for doing
nothing and exploiting others, why should man, its descendant,
show greater scruples? The principle that idleness is the mother of
prosperity would carry us far indeed. I have said enough on my own
account; I will call upon the animals themselves, more eloquent than I.
Are we so very sure that parasitic habits come from a love of inaction?
Did the parasite become what he is because he found it excellent to
do nothing? Is repose so great an advantage to him that he abjured his
ancient customs in order to obtain it? Well, since I have been studying
the Bee who endows her family with the property of others, I have not
yet seen anything in her that points to slothfulness. On the contrary,
the parasite leads a laborious life, harder than that of the worker.
Watch her on a slope blistered by the sun. How busy she is, how
anxious! How briskly she covers every inch of the radiant expanse, how
indefatigable she is in her endless quests; in her visits, which are
generally fruitless! Before coming upon a nest that suits her, she has
dived a hundred times into cavities of no value, into galleries not
yet victualled. And then, however kindly her host, the parasite is not
always well received in the hostelry. No, it is not all roses in her
trade. The expenditure of time and labour which she finds necessary in
order to house an egg may easily equal or even exceed that of the worker
in building her cell and filling it with honey. That industrious one has
regular and continuous work, an excellent condition for success in her
egg-laying; the other has a thankless and precarious task, at the
mercy of a thousand accidents which endanger the great undertaking of
installing the eggs. One has only to watch the prolonged hesitation of
a Coelioxys seeking for the Leaf-cutters' cells to recognize that
the usurpation of another's nest is not effected without serious
difficulties. If she turned parasite in order to make the rearing of
her offspring easier and more prosperous, certainly she was very
ill-inspired. Instead of rest, hard work; instead of a flourishing
family, a meagre progeny.
To generalities, which are necessarily vague, we will add some precise
facts. A certain Stelis (Stelis nasuta, LATR.) is a parasite of the
Mason-bee of the Walls. When the Chalicodoma has finished building
her dome of cells upon her pebble, the parasite appears, makes a long
inspection of the outside of the home and proposes, puny as she is,
to introduce her eggs into this cement fortress. Everything is most
carefully closed: a layer of rough plaster, at least two-fifths of an
inch thick, entirely covers the central accumulation of cells, which
are each of them sealed with a thick mortar plug. And it is the honey
of these well-guarded chambers that has to be reached by piercing a wall
almost as hard as rock.
The parasite pluckily sets to; the idler becomes a glutton for work.
Atom by atom, she perforates the general enclosure and scoops out a
shaft just sufficient for her passage; she reaches the lid of the cell
and gnaws it until the coveted provisions appear in sight. It is a slow
and painful process, in which the feeble Stelis wears herself out, for
the mortar is much the same as Roman cement in hardness. I myself find
a difficulty in breaking it with the point of my knife. What patient
effort, then, the task requires from the parasite, with her tiny
pincers!
I do not know exactly how long the Stelis takes to make her
entrance-shaft, as I have never had the opportunity or rather the
patience to follow the work from start to finish; but what I do know is
that a Chalicodoma of the Walls, incomparably larger and stronger than
the parasite, when demolishing before my eyes the lid of a cell sealed
only the day before, was unable to complete her undertaking in one
afternoon. I had to come to her assistance in order to discover,
before the end of the day, the object of her housebreaking. When the
Mason-bee's mortar has once set, its resistance is that of stone. Now
the Stelis has not only to pierce the lid of the honey-store; she must
also pierce the general casing of the nest. What a time it must take her
to get through such a task, a gigantic one for her poor tools!
It is done at last, after infinite labour. The honey appears. The Stelis
slips through and, on the surface of the provisions, side by side
with the Chalicodoma's eggs, the number varying from time to time. The
victuals will be the common property of all the new arrivals, whether
the son of the house or strangers.
The violated dwelling cannot remain as it is, exposed to marauders from
without; the parasite must herself wall up the breach which she has
contrived. The quondam housebreaker becomes a builder. At the foot
of the pebble, the Stelis collects a little of that red earth which
characterizes our stony plateaus grown with lavender and thyme; she
makes it into mortar by wetting it with saliva; and with the pellets
thus prepared she fills up the entrance-shaft, displaying all the care
and art of a regular master-mason. Only, the work clashes in colour with
the Chalicodoma's. The Bee goes and gathers her cementing-powder on the
adjoining high-road, the metal of which consists of broken flint-stones,
and very seldom uses the red earth under the pebble supporting the
nest. This choice is apparently dictated by the fact that the chemical
properties of the former are more likely to produce a solid structure.
The lime of the road, mixed with saliva, yields a harder cement than red
clay would do. At any rate, the Chalicodoma's nest is more or less
white because of the source of its materials. When a red speck, a few
millimetres wide, appears on this pale background, it is a sure sign
that a Stelis has been that way. Open the cell that lies under the red
stain: we shall find the parasite's numerous family established there.
The rusty spot is an infallible indication that the dwelling has been
violated: at least, it is so in my neighbourhood, where the soil is as I
have described.
We see the Stelis, therefore, at first a rabid miner, using her
mandibles against the rock; next a kneader of clay and a plasterer
restoring broken ceilings. Her trade does not seem one of the least
arduous. Now what did she do before she took to parasitism? Judging from
her appearance, the transformists tell us that she was an Anthidium,
that is to say, she used to gather the soft cotton-wool from the dry
stalks of the lanate plants and fashion it into wallets, in which to
heap up the pollen-dust which she gleaned from the flowers by means of
a brush carried on her abdomen. Or else, springing from a genus akin
to the cotton-workers, she used to build resin partitions in the spiral
stairway of a dead Snail. Such was the trade driven by her ancestors.
Really! So, to avoid slow and painful work, to achieve an easy life, to
give herself the leisure favourable to the settlement of her family,
the erstwhile cotton-presser or collector of resin-drops took to gnawing
hardened cement! She who once sipped the nectar of flowers made up her
mind to chew concrete! Why, the poor wretch toils at her filing like a
galley-slave! She spends more time in ripping up a cell than it would
take her to make a cotton wallet and fill it with food. If she really
meant to progress, to do better in her own interest and that of her
family, by abandoning the delicate occupations of the old days, we must
confess that she has made a strange mistake. The mistake would be no
greater if fingers accustomed to fancy-weaving were to lay aside velvet
and silk and proceed to handle the quarryman's blocks or to break stones
on the roadside.
No, the animal does not commit the folly of voluntarily embittering its
lot; it does not, in obedience to the promptings of idleness, give up
one condition to embrace another and a more irksome; should it blunder
for once, it will not inspire its posterity with a wish to persevere in
a costly delusion. No, the Stelis never abandoned the delicate art of
cotton-weaving to break down walls and to grind cement, a class of work
far too unattractive to efface the memory of the joys of harvesting amid
the flowers. Indolence has not evolved her from an Anthidium. She has
always been what she is to-day: a patient artificer in her own line, a
steady worker at the task that has fallen to her share.
That hurried mother who first, in remote ages, broke into the abode
of her fellows to secure a home for her eggs found this unscrupulous
method, so you tell us, very favourable to the success of her race, by
virtue of its economy of time and trouble. The impression left by this
new policy was so profound that heredity bequeathed it to posterity,
in ever-increasing proportions, until at last parasitic habits became
definitely fixed. The Chalicodoma of the Sheds, followed by the
Three-horned Osmia, will teach us what to think of this conjecture.
I have described in an earlier chapter my installation of
Chalicodoma-hives against the walls of a porch facing the south. Here,
on a level with my head, placed so that they can easily be observed,
hang some tiles removed from the neighbouring roofs in winter, together
with their enormous nests and their occupants. Every May, for five or
six years in succession, I have assiduously watched the works of
my Mason-bees. From the mass of my notes on the subject I take the
following experiments which bear upon the matter under discussion.
Long ago, when I used to scatter a handful of Chalicodomae some way from
home, in order to study their capacity for finding their nest again,
I noticed that, if they were too long absent, the laggards found their
cells closed on their return. Neighbours had taken the opportunity to
lay their eggs there, after finishing the building and stocking it with
provisions. The abandoned property benefited another. On realizing
the usurpation, the Bee returning from her long journey soon consoled
herself for the mishap. She began to break the seals of some cell or
other, adjoining her own; the rest let her have her way, being
doubtless too busy with their present labours to seek a quarrel with the
freebooter. As soon as she had destroyed the lid, the Bee, with a sort
of feverish haste that burned to repay theft by theft, did a little
building, did a little victualling, as though to resume the thread of
her occupations, destroyed the egg in being, laid her own and closed
the cell again. Here was a touch of nature that deserved careful
examination.
At eleven o'clock in the morning, when the work is at its height, I mark
half-a-score of Chalicodomae with different colours, to distinguish them
from one another. Some are occupied with building, others are disgorging
honey. I mark the corresponding cells in the same way. As soon as the
marks are quite dry, I catch the ten Bees, place them singly in screws
of paper and shut them all in a box until the next morning. After
twenty-four hours' captivity, the prisoners are released. During
their absence, their cells have disappeared under a layer of recent
structures; or, if still exposed to view, they are closed and others
have made use of them.
As soon as they are free, the ten Bees, with one exception, return to
their respective tiles. They do more than this, so accurate is their
memory, despite the confusion resulting from a prolonged incarceration:
they return to the cell which they have built, the beloved stolen cell;
they minutely explore the outside of it, or at least what lies nearest
to it, if the cell has disappeared under the new structures. In cases
where the home is not henceforward inaccessible, it is at least occupied
by a strange egg and the door is securely fastened. To this reverse of
fortune the ousted ones retort with the brutal lex talionis: an egg for
an egg, a cell for a cell. You've stolen my house; I'll steal yours.
And, without much hesitation, they proceed to force the lid of a cell
that suits them. Sometimes they recover possession of their own home, if
it is possible to get into it; sometimes and more frequently they
seize upon some one else's, even at a considerable distance from their
original dwelling.
Patiently they gnaw the mortar lid. As the general rough-cast covering
all the cells is not applied until the end of the work, all that they
need do is to demolish the lid, a hard and wearisome task, but not
beyond the strength of their mandibles. They therefore attack the door,
the cement disk, and reduce it to dust. The criminal is allowed to carry
out her nefarious designs without the slightest interference or protest
from any of her neighbours, though these must necessarily include the
chief party interested. The Bee is as forgetful of her cell of yesterday
as she is jealous of her actual cell. To her the present is everything;
the past means nothing; and the future means no more. And so the
population of the tile leave the breakers of doors to do their business
in peace; none hastens to the defence of a home that might well be her
own. How differently things would happen if the cell were still on the
stocks! But it dates back to yesterday, to the day before; and no one
gives it another thought.
It's done: the lid is demolished; access is free. For some time, the Bee
stands bending over the cell, her head half-buried in it, as though in
contemplation. She goes away, she returns undecidedly; at last she makes
up her mind. The egg is snapped up from the surface of the honey and
flung on the rubbish-heap with no more ceremony than if the Bee were
ridding the house of a bit of dirt. I have witnessed this hideous crime
again and yet again; I confess to having repeatedly provoked it. In
housing her egg, the Mason-bee displays a brutal indifference to the
fate of her neighbour's egg.
I see some of them afterwards busy provisioning, disgorging honey and
brushing pollen into the cell already completely provisioned; I see some
masoning a little at the orifice, or at least laying on a few trowels of
mortar. It seems as if the Bee, although the victuals and the building
are just as they should be, were resuming the work at the point at which
she left it twenty-four hours before. Lastly, the egg is laid and the
opening closed up. Of my captives, one, less patient than the rest,
rejects the slow process of eating away the cover and decides in favour
of robbery with violence, on the principle that might is right. She
dislodges the owner of a half-stocked cell, keeps good watch for a
long time on the threshold of the home and, when she feels herself
the mistress of the house, goes on with the provisioning. I follow the
ousted proprietress with my eyes. I see her seize upon a closed cell
by breaking into it, behaving in all respects like my imprisoned
Chalicodomae.
The whole occurrence was too significant to be left without further
confirmation. I repeated the experiment, therefore, almost every year,
always with the same success. I can only add that, among the Bees placed
by my artifices under the necessity of making up for lost time, a few
are of a more easy-going temperament. I see some building anew, as
if nothing out of the way had happened; others--this is a very rare
course--going to settle on another tile, as though to avoid a society
of thieves; and lastly a few who bring pellets of mortar and zealously
finish the lid of their own cell, although it contains a strange egg.
However, housebreaking is the usual thing.
One more detail not without value: it is not necessary for you to
intervene and imprison Mason-bees for a time in order to witness the
acts of violence which I have described. If you follow the work of the
swarm assiduously, you may occasionally find a surprise awaiting you. A
Mason-bee will appear and, for no reason known to you, break open a door
and lay her egg in the violated cell. From what goes before, I look upon
the Bee as a laggard, kept away from the workyard by an accident, or
else carried to a distance by a gust of wind. On returning after an
absence of some duration, she finds her place taken, her cell used by
another. The victim of an usurper's villainy, like the prisoners in my
paper screws, she behaves as they do and indemnifies herself for her
loss by breaking into another's home.
Lastly, it was a matter of learning the behaviour, after their act of
violence, of the Masons who have smashed in a door, brutally expelled
the egg within and replaced it by one of their own laying. When the lid
is repaired to look as good as new and everything restored to order,
will they continue their burglarious ways and exterminate the eggs of
others to make room for their own? By no means. Revenge, that pleasure
of the gods and perhaps also of Bees, is satisfied after one cell has
been ripped open. All anger is appeased when the egg for which so much
work has been done is safely housed. Henceforth, both prisoners and
stray laggards resume their ordinary labours, indifferently with the
rest. They build honestly, they provision honestly, nor meditate further
evil. The past is quite forgotten until a fresh disaster occurs.
To return to the parasites: a mother chanced to find herself the
mistress of another's nest. She took advantage of this to entrust
her egg to it. This expeditious method, so easy for the mother and so
favourable to the success of her offspring, made such an impression on
her that she transmitted the maternal indolence to her posterity. Thus
the worker gradually became transformed into a parasite.
Capital! The thing goes like clockwork, as long as we have only to put
our ideas on paper. But let us just consult the facts, if you don't
mind; before arguing about probabilities, let us look into things as
they are. Here is the Mason-bee of the Sheds teaching us something very
curious. To smash the lid of a cell that does not belong to her, to
throw the egg out of doors and put her own in its place is a practice
which she has followed since time began. There is no need of my
interference to make her commit burglary: she commits it of her own
accord, when her rights are prejudiced as the result of a too-long
absence. Ever since her race has been kneading cement, she has known the
law of retaliation. Countless ages, such as the evolutionists require,
have made her adopt forcible usurpation as an inveterate habit.
Moreover, robbery is so incomparably easy for the mother. No more cement
to scratch up with her mandibles on the hard ground, no more mortar to
knead, no more clay walls to build, no more pollen to gather on hundreds
and hundreds of journeys. All is ready, board and lodging. Never was a
better opportunity for allowing one's self a good time. There is
nothing against it. The others, the workers, are imperturbable in their
good-humour. Their outraged cells leave them profoundly indifferent.
There are no brawls to fear, no protests. Now or never is the moment to
tread the primrose path.
Besides, your progeny will be all the better for it. You can choose the
warmest and wholesomest spots; you can multiply your laying-operations
by devoting to them all the time that you would have to spend on irksome
occupations. If the impression produced by the violent seizure of
another's property is strong enough to be handed down by heredity, how
deep should be the impression of the actual moment when the Mason-bee
is in the first flush of success! The precious advantage is fresh in the
memory, dating from that very instant; the mother has but to continue
in order to create a method of installation favourable in the highest
degree to her and hers. Come, poor Bee! Throw aside your exhausting
labours, follow the evolutionists' advice and, as you have the means at
your disposal, become a parasite!
But no, having effected her little revenge, the builder returns to
her masonry, the gleaner to her gleaning, with unquenchable zeal. She
forgets the crime committed in a moment of anger and takes good care not
to hand down any tendency towards idleness to her offspring. She knows
too well that activity is life, that work is the world's great joy. What
myriads of cells has she not broken open since she has been building;
what magnificent opportunities, all so clear and conclusive, has she
not had to emancipate herself from drudgery! Nothing could convince her:
born to work, she persists in an industrious life. She might at least
have produced an offshoot, a race of housebreakers, who would invade
cells by demolishing doors. The Stelis does something of the kind; but
who would think of proclaiming a relationship between the Chalicodoma
and her? The two have nothing in common. I call for a scion of the
Mason-bee of the Sheds who shall live by the art of breaking through
ceilings. Until they show me one, the theorists will only make me smile
when they talk to me of erstwhile workers relinquishing their trade to
become parasitic sluggards.
I also call, with no less insistence, for a descendant of the
Three-horned Osmia, a descendant given to demolishing party-walls. I
will describe later how I managed to make a whole swarm of these Osmiae
build their nests on the table in my study, in glass tubes that enabled
me to see the inmost secrets of the work of the Bee. (Cf. "Bramble-bees
and Others", by J. Henri Fabre, translated by Alexander Teixeira de
Mattos: chapters 1 to 7.--Translator's Note.) For three or four weeks,
each Osmia is scrupulously faithful to her tube, which is laboriously
filled with a set of chambers divided by earthen partitions. Marks of
different colours painted on the thorax of the workers enable me
to recognize individuals in the crowd. Each crystal gallery is the
exclusive property of one Osmia; no other enters it, builds in it or
hoards in it. If, through heedlessness, through momentary forgetfulness
of her own house in the tumult of the city, some neighbour so much as
comes and looks in at the door, the owner soon puts her to flight. No
such indiscretion is tolerated. Every Bee has her home and every home
its Bee.
All goes well until just before the end of the work. The tubes are then
closed at the orifice with a thick plug of earth; nearly the whole swarm
has disappeared; there remain on the spot a score of tatterdemalions in
threadbare fleeces, worn out by a month's hard toil. These laggards have
not finished their laying. There is no lack of unoccupied tubes, for I
take care to remove some of those which are full and to replace them by
others that have not yet been used. Very few of the Bees decide to take
possession of these new homes, which differ in no particular from the
earlier ones; and even then they build only a small number of cells,
which are often mere attempts at partitions.
They want something different: a nest belonging to some one else. They
bore through the stopper of the inhabited tubes, a work of no great
difficulty, for we have here not the hard cement of the Chalicodoma, but
a simple lid of dried mud. When the entrance is cleared, a cell appears,
with its store of provisions and its egg, with her brutal mandibles; she
rips it open and goes and flings it away. She does worse: she eats it
on the spot. I had to witness this horror many times over before I could
accept it as a fact. Note that the egg devoured may very well contain
the criminal's own offspring. Imperiously swayed by the needs of her
present family, the Osmia puts her past family entirely out of her mind.
Having perpetrated this child-murder, the depraved creature does a
little provisioning. They all experience the same necessity to go
backwards in the sequence of actions in order to pick up the thread of
their interrupted occupations. Her next work is to lay her egg and then
she conscientiously restores the demolished lid.
The havoc can be more sweeping still. One of these laggards is not
satisfied with a single cell; she needs two, three, four. To reach
the most remote, the Osmia wrecks all those which come before it.
The partitions are broken down, the eggs eaten or thrown away, the
provisions swept outside and often even carried to a distance in great
lumps. Covered with dust from the loose plaster of the demolition,
floured all over with the rifled pollen, sticky with the contents of the
mangled eggs, the Osmia, while at her brigand's work, is altered beyond
recognition. Once the place is cleared, everything resumes its normal
course. Provisions are laboriously brought to take the place of those
which have been thrown away; eggs are laid, one on each heap of food;
the partitions are built up again; and the massive plug sealing the
whole structure is made as good as new.
Crimes of this kind recur so often that I am obliged to interfere and
place in safety the nests which I wish to keep intact. And nothing as
yet explains this brigandage, bursting forth at the end of the work like
a moral epidemic, like a frenzied delirium. I should say nothing if the
site were lacking; but the tubes are there, close by, empty and quite
fit to receive the eggs. The Osmia refuses them, she prefers to plunder.
Is it from weariness, from a distaste for work after a period of fierce
activity? Not at all; for, when a row of cells has been stripped of its
contents, after the ravage and waste, she has to come back to ordinary
work, with all its burdens. The labour is not reduced; it is increased.
It would pay the Bee infinitely better, if she wants to continue
her laying, to make her home in an unoccupied tube. The Osmia thinks
differently. Her reasons for acting as she does escape me. Can there
be ill-conditioned characters among her, characters that delight in a
neighbour's ruin? There are among men.
In the privacy of her native haunts, the Osmia, I have no doubt, behaves
as in my crystal galleries. Towards the end of the building-operations,
she violates others' dwellings. By keeping to the first cell, which it
is not necessary to empty in order to reach the next, she can utilize
the provisions on the spot and shorten to that extent the longest part
of her work. As usurpations of this kind have had ample time to become
inveterate, to become inbred in the race, I ask for a descendant of the
Osmia who eats her grandmother's egg in order to establish her own egg.
This descendant I shall not be shown; but I may be told that she is in
process of formation. The outrages which I have described are preparing
a future parasite. The transformists dogmatize about the past and
dogmatize about the future, but as seldom as possible talk to us about
the present. Transformations have taken place, transformations will take
place; the pity of it is that they are not actually taking place. Of the
three tenses, one is lacking, the very one which directly interests us
and which alone is clear of the incubus of theory. This silence about
the present does not please me overmuch, scarcely more than the famous
picture of "The Crossing of the Red Sea" painted for a village chapel.
The artist had put upon the canvas a broad ribbon of brightest scarlet;
and that was all.
'Yes, that's the Red Sea,' said the priest, examining the masterpiece
before paying for it. 'That's the Red Sea, right enough; but where are
the Israelites?'
'They have passed,' replied the painter.
'And the Egyptians?'
'They are on the way.'
Transformations have passed, transformations are on the way. For mercy's
sake, cannot they show us transformations in the act? Must the facts of
the past and the facts of the future necessarily exclude the facts of
the present? I fail to understand.
I call for a descendant of the Chalicodoma and a descendant of the Osmia
who have robbed their neighbours with gusto, when occasion offered,
since the origin of their respective races, and who are working
industriously to create a parasite happy in doing nothing. Have they
succeeded? No. Will they succeed? Yes, people maintain. For the moment,
nothing. The Osmiae and Chalicodomae of to-day are what they were when
the first trowel of cement or mud was mixed. Then how many ages does it
take to form a parasite? Too many, I fear, for us not to be discouraged.
If the sayings of the theorists are well-founded, going on strike and
living by shifts was not always enough to assure parasitism. In certain
cases, the animal must have had to change its diet, to pass from live
prey to vegetarian fare, which would entirely subvert its most essential
characteristics. What should we say to the Wolf giving up mutton and
browsing on grass, in obedience to the dictates of idleness? The boldest
would shrink from such an absurd assumption. And yet transformism leads
us straight to it.
Here is an example: in July, I split some bramble-stems in which Osmia
tridentata has built her nests. In the long series of cells, the lower
already hold the Osmia's cocoons, while the upper contain the larva
which has nearly finished consuming its provisions and the topmost
show the victuals untouched, with the Osmia's egg upon them. It is a
cylindrical egg, rounded at both extremities, of a transparent white
and measuring four to five millimetres in length. (.156 to.195
inch.--Translator's Note.) It lies slantwise, one end of it resting on
the food and the other sticking up at some distance above the honey.
Now, by multiplying my visits to the fresh cells, I have on several
occasions made a very valuable discovery. On the free end of the Osmia's
egg, another egg is fixed; an egg quite different in shape, white and
transparent like the first, but much smaller and narrower, blunt at
one end and tapering into a rather sharp point at the other. It is
two millimetres long by half a millimetre wide. (.078 and.019
inch.--Translator's Note.) It is undeniably the egg of a parasite, a
parasite which compels my attention by its curious method of installing
its family.
It opens before the Osmia's egg. The tiny grub, as soon as it is born,
begins to drain the rival egg, of which it occupied the top part, high
up above the honey. The extermination soon becomes perceptible. You can
see the Osmia's egg turning muddy, losing its brilliancy, becoming limp
and wrinkled. In twenty-four hours, it is nothing but an empty sheath,
a crumpled bit of skin. All competition is now removed; the parasite is
the master of the house. The young grub, when demolishing the egg, was
active enough: it explored the dangerous thing which had to be got
rid of quickly, it raised its head to select and multiply the
attacking-points. Now, lying at full length on the surface of the honey,
it no longer shifts its position; but the undulations of the digestive
canal betray its greedy absorption of the Osmia's store of food. The
provisions are finished in a fortnight and the cocoon is woven. It is
a fairly firm ovoid, of a very dark-brown colour, two characteristics
which at once distinguish it from the Osmia's pale, cylindrical cocoon.
The hatching takes place in April or May. The puzzle is solved at
last: the Osmia's parasite is a Wasp called the Spotted Sapyga (Sapyga
punctata, V.L.)
Now where are we to class this Wasp, a true parasite in the strict
sense of the word, that is to say, a consumer of others' provisions. Her
general appearance and her structure make it clear to any eye more or
less familiar with entomological shapes that she belongs to a species
akin to that of the Scoliae. Moreover, the masters of classification, so
scrupulous in their comparison of characteristics, agree in placing the
Sapygae immediately after the Scoliae and a little before the Mutillae.
The Scoliae feed their grubs on prey; so do the Mutillae. The Osmia's
parasite, therefore, if it really derives from a transformed ancestor,
is descended from a flesh-eater, though it is now an eater of honey. The
Wolf does more than become a Sheep: he turns himself into a sweet-tooth.
'You will never get an apple-tree out of an acorn,' Franklin tells us,
with that homely common-sense of his.
In this case, the passion for jam must have sprung from a love of
venison. Any theory might well be deficient in balance when it leads to
such vagaries as this.
I should have to write a volume if I would go on setting forth my
doubts. I have said enough for the moment. Man, the insatiable enquirer,
hands down from age to age his questions about the whys and wherefores
of origins. Answer follows answer, is proclaimed true to-day and
recognized as false tomorrow; and the goddess Isis continues veiled.