More Hunting Wasps
by
J. Henri Fabre

Part 2 out of 4

Wasps": chapters 1 to 3.--Translator's Note.), prey exclusively on the
Weevils and the Buprestes, that is, on the families whose nervous system
presents a degree of concentration which may be compared with that of the
Scolia's victims. Those predatory insects, working in the open air, are
exempt from the difficulties which their emulators, working underground,
have to overcome. Their movements are free and are directed by the sense of
sight; but their surgery is confronted in another respect with a most
arduous problem.

The victim, a Beetle, is covered at all points with a suit of armour which
the sting is unable to penetrate. The joints alone will allow the poisoned
lancet to pass. Those of the legs do not in any way comply with the
conditions imposed: the result of stinging them would be merely a partial
disorder which far from subduing the insect, would render it more dangerous
by irritating it yet further. A sting in the joint of the neck is not
admissible: it would injure the cervical ganglia and lead to death,
followed by putrefaction. There remains only the joint between the corselet
and the abdomen.

The sting, in entering here, has to abolish all movement with a single
stab, for any movement would imperil the rearing of the larva. The success
of the paralysis, therefore, demands that the motor ganglia, at least the
three thoracic ganglia, shall be packed in close contact opposite this
point. This determines the selection of Weevils and Buprestes, both of
which are so strongly armoured.

But where the prey has only a soft skin, incapable of stopping the sting,
the concentrated nervous system is no longer necessary, for the operator,
versed in the anatomical secrets of her victim, knows to perfection where
the centres of innervation lie; and she wounds them one after another, if
need be from the first to the last. Thus do the Ammophilae go to work when
dealing with their caterpillars and the Sphex-wasps when dealing with their
Locusts, Ephippigers and Crickets.

With the Scoliae we come once again to a soft prey, with a skin penetrable
by the sting no matter where it be attacked. Will the tactics of the
caterpillar-hunters, who stab and stab again, be repeated here? No, for the
difficulty of movement under ground prohibits so complicated an operation.
Only the tactics of the paralysers of armour-clad insects are practicable
now, for, since there is but one thrust of the dagger, the feat of surgery
is reduced to its simplest terms, a necessary consequence of the
difficulties of an underground operation. The Scoliae, then, whose destiny
it is to hunt and paralyse under the soil the victuals for their family,
require a prey made highly vulnerable by the close assemblage of the nerve-
centres, as are the Weevils and Buprestes of the Cerceres; and this is why
it has fallen to their lot to share among them the larvae of the
Scarabaeidae.

Before they obtained their allotted portion, so closely restricted and so
judiciously selected; before they discovered the precise and almost
mathematical point at which the sting must enter to produce a sudden and a
lasting immobility; before they learnt how to consume, without incurring
the risk of putrefaction, so corpulent a prey: in brief, before they
combined these three conditions of success, what did the Scoliae do?

The Darwinian school will reply that they were hesitating, essaying,
experimenting. A long series of blind gropings eventually hit upon the most
favourable combination, a combination henceforth to be perpetuated by
hereditary transmission. The skilful co-ordination between the end and the
means was originally the result of an accident.

Chance! A convenient refuge! I shrug my shoulders when I hear it invoked to
explain the genesis of an instinct so complex as that of the Scoliae. In
the beginning, you say, the creature gropes and feels its way; there is
nothing settled about its preferences. To feed its carnivorous larvae it
levies tribute on every species of game which is not too much for the
huntress' power or the nurseling's appetite; its descendants try now this,
now that, now something else, at random, until the accumulated centuries
lead to the selection which best suits the race. Then habit grows fixed and
becomes instinct.

Very well. Let us agree that the Scolia of antiquity sought a different
prey from that adopted by the modern huntress. If the family throve upon a
diet now discontinued, we fail to see that the descendants had any reason
to change it: animals have not the gastronomic fancies of an epicure whom
satiety makes difficult to please. Because the race did well upon this
fare, it became habitual; and instinct became differently fixed from what
it is to-day. If, on the other hand, the original food was unsuitable, the
existence of the family was jeopardized; and any attempt at future
improvement became impossible, because an unhappily inspired mother would
leave no heirs.

To escape falling into this twofold trap, the theorists will reply that the
Scoliae are descended from a precursor, an indeterminate creature, of
changeable habits and changing form, modifying itself in accordance with
its environment and with the regional and climatic conditions and branching
out into races each of which has become a species with the attributes which
distinguish it to-day. The precursor is the deus ex machina of evolution.
When the difficulty becomes altogether too importunate, quick, a precursor,
to fill up the gaps, quick, an imaginary creature, the nebulous plaything
of the mind! This is seeking to lighten the darkness with a still deeper
obscurity; to illumine the day by piling cloud upon cloud. Precursors are
easier to find than sound arguments. Nevertheless, let us put the precursor
of the Scoliae to the test.

What did she do? Being capable of everything, she did a bit of everything.
Among its descendants were innovators who developed a taste for tunnelling
in sand and vegetable mould. There they encountered the larvae of the
Cetonia, the Oryctes, the Anoxia, succulent morsels on which to rear their
families. By degrees the indeterminate Wasp adopted the sturdy proportions
demanded by underground labour. By degrees she learnt to stab her plump
neighbours in scientific fashion; by degrees she acquired the difficult art
of consuming her prey without killing it; at length, by degrees, aided by
the richness of her diet, she became the powerful Scolia with whom we are
familiar. Having reached this point, the species assumes a permanent form,
as does its instinct.

Here we have a multiplicity of stages, all of the slowest, all of the most
incredible nature, whereas the Wasp cannot found a race except on the
express condition of complete success from the first attempt. We will not
insist further upon the insurmountable objection; we will admit that, amid
so many unfavourable chances, a few favoured individuals survive, becoming
more and more numerous from one generation to the next, in proportion as
the dangerous art of rearing the young is perfected. Slight variations in
one and the same direction form a definite whole; and at long last the
ancient precursor has become the Scolia of our own times.

By the aid of a vague phraseology which juggles with the secret of the
centuries and the unknown things of life, it is easy to build up a theory
in which our mental sloth delights, after being discouraged by difficult
researches whose final result is doubt rather than positive statement. But
if, so far from being satisfied with hazy generalities and adopting as
current coin the terms consecrated by fashion, we have the perseverance to
explore the truth as far as lies in our power, the aspect of things will
undergo a great change and we shall discover that they are far less simple
than our overprecipitate views declared them to be. Generalization is
certainly a most valuable instrument: science indeed exists only by virtue
of it. Let us none the less beware of generalizations which are not based
upon very firm and manifold foundations.

When these foundations are lacking, the child is the great generalizer. For
him, the feathered world consists merely of birds; the race of reptiles
merely of snakes, the only difference being that some are big and some are
little. Knowing nothing, he generalizes in the highest degree; he
simplifies, in his inability to perceive the complex. Later he will learn
that the Sparrow is not the Bullfinch, that the Linnet is not the
Greenfinch; he will particularize and to a greater degree each day, as his
faculty of observation becomes more fully trained. In the beginning he saw
nothing but resemblances; he now sees differences, but still not plainly
enough to avoid incongruous comparisons.

In his adult years he will almost to a certainty commit zoological blunders
similar to those which my gardener retails to me. Favier, an old soldier,
has never opened a book, for the best of reasons. He barely knows how to
cipher: arithmetic rather than reading is forced upon us by the brutalities
of life. Having followed the flag over three-quarters of the globe, he has
an open mind and a memory crammed with reminiscences, which does not
prevent him, when we chat about animals, from making the most crazy
assertions. For him the Bat is a Rat that has grown wings; the Cuckoo is a
Sparrow-hawk retired from business; the Slug is a Snail who has lost his
shell with the advance of years; the Nightjar (Known also as the
Goatsucker, because of the mistaken belief that the bird sucks the milk of
Goats, and, in America, as the Whippoorwill.--Translator's Note.), the
Chaoucho-grapaou, as he calls her, is an elderly Toad, who, becoming
enamoured of milk-food, has grown feathers, so that she may enter the byres
and milk the Goats. It is impossible to drive these fantastic ideas out of
his head. Favier himself, as will be seen, is an evolutionist after his own
fashion, an evolutionist of a very daring type. In accounting for the
origin of animals nothing gives him pause. He has a reply to everything:
"this" comes from "that." If you ask him why, he answers:

"Look at the resemblance!"

Shall we reproach him with these insanities, when we hear another, misled
by the Monkey's build, acclaim the Pithecanthropus as man's precursor?
Shall we reject the metamorphosis of the Chaoucho-grapaou, when people tell
us in all seriousness that, in the present stage of scientific knowledge,
it is absolutely proved that man is descended from some rough-hewn Ape? Of
the two transformations, Favier's strikes me as the more credible. A
painter of my acquaintance, a brother of the great composer Felicien David
(Felicien Cesar David (1810-1876). His chief work was the choral symphony
"Le Desert":--Translator's Note.), favoured me one day with his reflections
on the human structure:

"Ve, moun bel ami," he said. "Ve, l'home a lou dintre d'un por et lou
defero d'uno mounino." "See, my dear friend, see: man has the inside of a
pig and the outside of a monkey."

I recommend the painter's aphorism to those who might like to discover
man's origin in the Hog when the Ape has gone out of fashion. According to
David, descent is proved by internal resemblances:

"L'home a lou dintre d'un por."

The inventory of precursory types sees nothing but organic resemblances and
disdains the differences of aptitude. By consulting only the bones, the
vertebrae, the hair, the nervures of the wings, the joints of the antennae,
the imagination may build up any sort of genealogical tree that will fit
with our theories of classification, for, when all is said, the animal, in
its widest generalization, is represented by a digestive tube. With this
common factor, the way lies open to every kind of error. A machine is
judged not by this or that train of wheels, but by the nature of the work
accomplished. The monumental roasting-jack of a waggoners' inn and a
Breguet chronometer both have trains of cogwheels geared in almost a
similar fashion. (Louis Breguet (1803-1883), a famous Parisian watchmaker
and physicist.--Translator's Note.) Are we to class the two mechanisms
together? Shall we forget that the one turns a shoulder of mutton before
the hearth, while the other divides time into seconds?

In the same way, the organic scaffolding is dominated from on high by the
aptitudes of the animal, especially that superior characteristic, the
psychical aptitudes. That the Chimpanzee and the hideous Gorilla possess
close resemblances of structure to our own is obvious. But let us for a
moment consider their aptitudes. What differences, what a dividing gulf!
Without exalting ourselves as high as the famous reed of which Pascal
speaks, that reed which, in its weakness, by the mere fact that it knows
itself to be crushed, is superior to the world that crushes it, we may at
least ask to be shown, somewhere, an animal making an implement, which will
multiply its skill and its strength, or taking possession of fire, the
primordial element of progress. (Blaise Pascal(1623-1662). The allusion is
to a passage in the philosopher's "Pensees." Pascal describes man as a
reed, the weakest thing in nature, but "a thinking reed."--Translator's
Note.) Master of implements and of fire! These two aptitudes, simple though
they be, characterize man better than the number of his vertebrae and his
molars.

You tell us that man, at first a hairy brute, walking on all fours, has
risen on his hind-legs and shed his fur; and you complacently demonstrate
how the elimination of the hairy pelt was effected. Instead of bolstering
up a theory with a handful of fluff gained or lost, it would perhaps be
better to settle how the original brute became the possessor of implements
and fire. Aptitudes are more important than hair; and you neglect them
because it is there that the insurmountable difficulty really resides. See
how the great master of evolution hesitates and stammers when he tries, by
fair means or foul, to fit instinct into the mould of his formulae. It is
not so easy to handle as the colour of the pelt, the length of the tail,
the ear that droops or stands erect. Yes, our master well knows that this
is where the shoe pinches! Instinct escapes him and brings his theory
crumbling to the ground.

Let us return to what the Scoliae teach us on this question, which
incidentally touches on our own origin. In conformity with the Darwinian
ideas, we have accepted an unknown precursor, who by dint of repeated
experiment, adopted as the victuals to be hoarded the larvae of the
Scarabaeidae. This precursor, modified by varying circumstances, is
supposed to have subdivided herself into ramifications, one of which,
digging into vegetable mould and preferring the Cetonia to any other game
inhabiting the same heap, became the Two-banded Scolia; another, also
addicted to exploring the soil, but selecting the Oryctes, left as its
descendant the Garden Scolia; and a third, establishing itself in sandy
ground, where it found the Anoxia, was the ancestress of the Interrupted
Scolia. To these three ramifications we must beyond a doubt add others
which complete the series of the Scolia. As their habits are known to me
only by analogy, I confine myself to mentioning them.

The three species at least, therefore, with which I am familiar would
appear to be derived from a common precursor. To traverse the distance from
the starting-point to the goal, all three have had to contend with
difficulties, which are extremely grave if considered one by one and are
aggravated even more by this circumstance, that the overcoming of one would
lead to nothing unless the others were surmounted as successfully. Success,
then, is contingent upon a series of conditions, each one of which offers
almost no chance of victory, so that the fulfilment of them all becomes a
mathematical absurdity if we are to invoke accident alone.

And, in the first place, how was it that the Scolia of antiquity, having to
provide rations for her carnivorous family, adopted for her prey only those
larvae which, owing to the concentration of their nervous systems, form so
remarkable and so rare an exception in the insect order? What chance would
hazard offer her of obtaining this prey, the most suitable of all because
the most vulnerable? The chance represented by unity compared with the
indefinite number of entomological species. The odds are as one to
immensity.

Let us continue. The larva of the Scarabaeid is snapped up underground, for
the first time. The victim protests, defends itself after its fashion,
coils itself up and presents to the sting on every side a surface on which
a wound entails no serious danger. And yet the Wasp, an absolute novice,
has to select, for the thrust of its poisoned weapon, one single point,
narrowly restricted and hidden in the folds of the larva's body. If she
miscalculates, she may be killed: the larva, irritated by the smarting
puncture, is strong enough to disembowel her with the tusks of its
mandibles. If she escapes the danger, she will nevertheless perish without
leaving any offspring, since the necessary provisions will be lacking.
Salvation for herself and her race depends on this: whether at the first
thrust she is able to reach the little nervous plexus which measures barely
one-fiftieth of an inch in width. What chance has she of plunging her
lancet into it, if there is nothing to guide her? The chance represented by
unity compared with the number of points composing the victim's body. The
odds are as one against immensity.

Let us proceed still further. The sting has reached the mark; the fat grub
is deprived of movement. At what spots should the egg now be laid? In
front, behind, on the sides, the back or the belly? The choice is not a
matter of indifference. The young grub will pierce the skin of its
provender at the very spot on which the egg was fixed; and, once an opening
is made, it will go ahead without hesitation. If this point of attack is
ill-chosen, the nurseling runs the risk of presently finding under its
mandibles some essential organ, which should have been respected until the
end in order to keep the victuals fresh. Remember how difficult it is to
complete the rearing when the tiny larva is moved from the place chosen by
the mother. The game promptly becomes putrid and the Scolia dies.

It is impossible for me to state the precise motives which lead to the
adoption of the spot on which the egg is laid; I can perceive general
reasons, but the details escape me, as I am not well enough versed in the
more delicate questions of anatomy and entomological physiology. What I do
know with absolute certainty is that the same spot is invariably chosen for
laying the egg. With not a single exception, on all the victims extracted
from the heap of garden mould--and they are numerous--the egg is fixed
behind the ventral surface, on the verge of the brown patch formed by the
contents of the digestive system.

If there be nothing to guide her, what chance has the mother of gluing her
egg to this point, which is always the same because it is that most
favourable to successful rearing? A very small point, represented by the
ratio of two or three square millimetres (About 1/100 square inch.--
Translator's Note.) to the entire surface of the victim's body.

Is this all? Not yet. The grub is hatched; it pierces the belly of the
Cetonia-larva at the requisite point; it plunges its long neck into the
entrails, ransacking them and filling itself to repletion. If it bite at
random, if it have no other guide in the selection of tit-bits than the
preference of the moment and the violence of an imperious appetite, it will
infallibly incur the danger of being poisoned by putrid food, for the
victim, if wounded in those organs which preserve a remnant of life in it,
will die for good and all at the first mouthfuls.

The ample joint must be consumed with prudent skill: this part must be
eaten before that and, after that, some other portion, always according to
method, until the time approaches for the last bites. This marks the end of
life for the Cetonia, but it also marks the end of the Scolia's feasting.
If the grub be a novice in the art of eating, if no special instinct guide
its mandibles in the belly of the prey, what chance has it of completing
its perilous meal? As much as a starving Wolf would have of daintily
dissecting his Sheep, when he tears at her gluttonously, rends her into
shreds and gulps them down.

These four conditions of success, with chance so near to zero in each case,
must all be realized together, or the grub will never be reared. The Scolia
may have captured a larva with close-packed nerve-centres, a Cetonia-grub,
for instance; but this will go for nothing unless she direct her sting
towards the only vulnerable point. She may know the whole secret of the art
of stabbing her victim, but this means nothing if she does not know where
to fasten her egg. The suitable spot may be found, but all the foregoing
will be useless if the grub be not versed in the method to be followed in
devouring its prey while keeping it alive. It is all or nothing.

Who would venture to calculate the final chance on which the future of the
Scolia, or of her precursor, is based, that complex chance whose factors
are four infinitely improbable occurrences, one might almost say four
impossibilities? And such a conjunction is supposed to be a fortuitous
result, to which the present instinct is due! Come, come!

>From another point of view again, the Darwinian theory is at variance with
the Scoliae and their prey. In the heap of garden mould which I exploited
in order to write this record, three kinds of larvae dwell together,
belonging to the Scarabaeid group: the Cetonia, the Oryctes and Scarabeus
pentodon. Their internal structure is very nearly similar; their food is
the same, consisting of decomposing vegetable matter; their habits are
identical: they live underground in tunnels which are frequently renewed;
they make a rough egg-shaped cocoon of earthy materials. Environment, diet,
industry and internal structure are all similar; and yet one of these three
larvae, the Cetonia's, reveals a most singular dissimilarity from its
fellow-trenchermen: alone among the Scarabaeidae and, more than that, alone
in all the immense order of insects, it walks upon its back.

If the differences were a matter of a few petty structural details, falling
within the finical department of the classifier, we might pass them over
without hesitation; but a creature that turns itself upside down in order
to walk with its belly in the air and never adopts any other method of
locomotion, though it possesses legs and good legs at that, assuredly
deserves examination. How did the animal acquire its fantastic mode of
progress and why does it think fit to walk in a fashion the exact contrary
of that adopted by other beasts?

To these questions the science now in fashion always has a reply ready:
adaptation to environment. The Cetonia-larva lives in crumbling galleries
which it bores in the depths of the soil. Like the sweep who obtains a
purchase with his back, loins and knees to hoist himself up the narrow
passage of a chimney, it gathers itself up, applies the tip of its belly to
one wall of its gallery and its sturdy back to another; and the combined
effort of these two levers results in moving it forward. The legs, which
are used very little, indeed hardly at all, waste away and tend to
disappear, as does any organ which is left unemployed; the back, on the
other hand, the principal motive agent, grows stronger, is furrowed with
powerful folds and bristles with grappling-hooks or hairs; and gradually,
by adaptation to its environment, the creature loses the art of walking,
which it does not practise, and replaces it by that of crawling on its
back, a form of progress better suited to underground corridors.

So far so good. But now tell me, if you please, why the larvae of the
Oryctes and the Scarabaeus, living in vegetable mould, the larva of the
Anoxia, dwelling in the sand, and the larva of the Cockchafer in our
cultivated fields have not also acquired the faculty of walking on their
backs? In their galleries they follow the chimney-sweep's methods quite as
cleverly as the Cetonia-grub; to move forward they make valiant use of
their backs without yet having come to ambling with their bellies in the
air. Can they have neglected to accommodate themselves to the demands of
their environment? If evolution and environment cause the topsy-turvy
progress of the one, I have the right, if words have any meaning whatever,
to demand as much of the others, since their organization is so much alike
and their mode of life identical.

I have but little respect for theories which, when confronted with two
similar cases, are unable to interpret the one without contradicting the
other. They make me laugh when they become merely childish. For example:
why has the tiger a coat streaked black and yellow? A matter of
environment, replies one of our evolutionary masters. Ambushed in bamboo
thickets where the golden radiance of the sun is intersected by stripes of
shadow cast by the foliage, the animal, the better to conceal itself,
assumed the colour of its environment. The rays of the sun produced the
tawny yellow of the coat; the stripes of shadow added the black bars.

And there you have it. Any one who refuses to accept the explanation must
be very hard to please. I am one of these difficult persons. If it were a
dinner-table jest, made over the walnuts and the wine, I would willingly
sing ditto; but alas and alack, it is uttered without a smile, in a solemn
and magisterial manner, as the last word in science! Toussenel, in his day,
asked the naturalists an insidious question. (Alphonse Toussenel (1803-
1885), the author of a number of learned and curious works on ornithology.-
-Translator's Note.) Why, he enquired, have Ducks a little curly feather on
the rump? No one, so far as I know, had an answer for the teasing cross-
examiner: evolution had not been invented then. In our time the reason why
would be forthcoming in a moment, as lucid and as well-founded as the
reason why of the tiger's coat.

Enough of childish nonsense. The Cetonia-grub walks on its back because it
has always done so. The environment does not make the animal; it is the
animal that is made for the environment. To this simple philosophy, which
is quite antiquated nowadays, I will add another, which Socrates expressed
in these words:

"What I know best is that I know nothing."

CHAPTER 6. THE TACHYTES.

The family of Wasps whose name I inscribe at the head of this chapter has
not hitherto, so far as I know, made much noise in the world. Its annals
are limited to methodical classifications, which make very poor reading.
The happy nations, men say, are those which have no history. I accept this,
but I also admit that it is possible to have a history without ceasing to
be happy. In the conviction that I shall not disturb its prosperity, I will
try to substitute the living, moving insect for the insect impaled in a
cork-bottomed box.

It has been adorned with a learned name, derived from the Greek Tachytes,
meaning rapidity, suddenness, speed. The creature's godfather, as we see,
had a smattering of Greek; its denomination is none the less unfortunate:
intended to instruct us by means of a characteristic feature, the name
leads us astray. Why is speed mentioned in this connection? Why a label
which prepares the mind for an exceptional velocity and announces a race of
peerless coursers? Nimble diggers of burrows and eager hunters the Tachytes
are, to be sure, but they are no better than a host of rivals. Not the
Sphex, nor the Ammophila, nor the Bembex, nor many another would admit
herself beaten in either flying or running. At the nesting-season, all this
tiny world of huntresses is filled with astounding activity. The quality of
a speedy worker being common to all, none can boast of it to the exclusion
of the rest.

Had I had a vote when the Tachytes was christened, I should have suggested
a short, harmonious, well-sounding name, meaning nothing else than the
thing meant. What better, for example, than the term Sphex? The ear is
satisfied and the mind is not corrupted by a prejudice, a source of error
to the beginner. I have not nearly as much liking for Ammophila, which
represents as a lover of the sands an animal whose establishments call for
compact soil. In short, if I had been forced, at all costs, to concoct a
barbarous appellation out of Latin or Greek in order to recall the
creature's leading characteristic, I should have attempted to say, a
passionate lover of the Locust.

Love of the Locust, in the broader sense of the Orthopteron, an exclusive,
intolerant love, handed down from mother to daughter with a fidelity which
the centuries fail to impair, this, yes, this indeed depicts the Tachytes
with greater accuracy than a name smacking of the race-course. The
Englishman has his roast-beef; the German his sauerkraut; the Russian his
caviare; the Neapolitan his macaroni; the Piedmontese his polenta; the man
of Carpentras his tian. The Tachytes has her Locust. Her national dish is
also that of the Sphex, with whom I boldly associate her. The methodical
classifier, who works in cemeteries and seems to fly the living cities,
keeps the two families far removed from each other because of
considerations and attaching to the nervures of the wings and the joints of
the palpi. At the risk of passing for a heretic, I bring them together at
the suggestion of the menu-card.

To my own knowledge, my part of the country possesses five species, one and
all addicted to a diet of Orthoptera. Panzer's Tachytes (T. Panzeri, VAN
DER LIND), girdled with red at the base of the abdomen, must be pretty
rare. I surprise her from time to time working on the hard roadside banks
and the trodden edges of the footpaths. There, to a depth of an inch at
most, she digs her burrows, each isolated from the rest. Her prey is an
adult, medium-sized Acridian (Locust or Grasshopper.--Translator's Note.),
such as the White-banded Sphex pursues. The captive of the one would not be
despised by the other. Gripped by the antennae, according to the ritual of
the Sphex, the victim is trailed along on foot and laid beside the nest,
with the head pointing towards the opening. The pit, prepared in advance,
is closed for the time being with a tiny flagstone and some bits of gravel,
in order to avoid either the invasion of a passer-by or obstruction by
landslips during the huntress' absence. A like precaution is taken by the
White-banded Sphex. Both observe the same diet and the same customs.

The Tachytes clears the entrance to the home and goes in alone. She
returns, puts out her head and, seizing her prey by the antennae,
warehouses it by dragging backwards. I have repeated, at her expense, the
tricks which I used to play on the Sphex. (For the author's experiments
with the Languedocian, the Yellow-winged and the White-edged Sphex, cf.
"The Hunting Wasps": chapter 11.--Translator's Note.) While the Tachytes is
underground, I move the game away. The insect comes up again and sees
nothing at its door; it comes out and goes to fetch its Locust, whom it
places in position as before. This done, it goes in again by itself. In its
absence I once more pull back the prey. Fresh emergence of the Wasp, who
puts things to rights and persists in going down again, still by herself,
however often I repeat the experiment. Yet it would be very easy for her to
put an end to my teasing: she would only have to descend straightway with
her game, instead of leaving it for a moment on her doorstep. But, faithful
to the usages of her race, she behaves as her ancestors behaved before her,
even though the ancient custom happen to be unprofitable. Like the Yellow-
winged Sphex, whom I have teased so often during her cellaring-operations,
she is a narrow conservative, learning nothing and forgetting nothing.

Let us leave her to do her work in peace. The Locust disappears underground
and the egg is laid upon the breast of the paralysed insect. That is all:
one carcase for each cell, no more. The entrance is stopped at last, first
with stones, which will prevent the trickling of the embankment into the
chamber; next with sweepings of dust, under which every vestige of the
subterranean house disappears. It is now done: the Tachytes will come here
no more. Other burrows will occupy her, distributed at the whim of her
vagabond humour.

A cell provisioned before my eyes on the 22nd of August, in one of the
walls in the harmas, contained the finished cocoon a week later. (The
harmas was the piece of enclosed waste land in which the author used to
study his insects in their natural state. Cf. "The Life of the Fly," by J.
Henri Fabre, translated by Alexander Teixeira de Mattos: chapter 1.--
Translator's Note.) I have not noted many examples of so rapid a
development. This cocoon recalls, in its shape and texture, that of the
Bembex-wasps. It is hard and mineralized, this is to say, the warp and woof
of silk are hidden by a thick encrustation of sand. This composite
structure seems to me characteristic of the family; at all events I find it
in the three species whose cocoons I know. If the Tachytes are nearly
related to the Spheges in diet, they are far removed from them in the
industry of their larvae. The first are workers in mosaic, encrusting a
network of silk and sand; the second weave pure silk.

Of smaller size and clad in black with trimmings of silvery down on the
edge of the abdominal segments, the Tarsal Tachytes frequents the ledges of
soft limestone in fairly populous colonies. (T. tarsina, LEP.) (According
to M. J. Perez, to whom I submitted the Wasp of which I am about to speak,
this Tachytes might well be a new species, if it is not Lepelletier's T.
tarsina or its equivalent, Panzer's T. unicolor. Any one wishing to clear
up this point will always recognize the quarrelsome insect by its
behaviour. A minute description seems useless to me in the type of
investigation which I am pursuing.--Author's Note.) August and September
are the season of her labours. Her burrows, very close to one another when
an easily-worked vein presents itself, afford an ample harvest of cocoons
once the site is discovered. In a certain gravel-pit in the neighbourhood,
with vertical walls visited by the sun, I have been able within a short
space of time to collect enough to fill the hollow of my hand completely.
They differ from the cocoons of the preceding species only in their smaller
size. The provisions consist of young Acridians, varying from about a
quarter to half an inch in length. The adult insect does not appear in the
assorted bags of game, being no doubt too tough for the feeble grub. All
the carcases consist of Locust-larvae, whose budding wings leave the back
uncovered and put one in mind of the short skirts of a skimpy jacket. Small
so that it may be tender, the game is numerous so that it may suffice all
needs. I count from two to four carcases to a cell. When the time comes we
will discover the reason for these differences in the rations served.

The Mantis-killing Tachytes wears a red scarf, like her kinswoman, Panzer's
Tachytes. (The Mantis-hunting Tachytes was submitted to examination by M.
J. Perez, who failed to recognize her. This species may well be new to our
fauna. I confine myself to calling her the Mantis-killing Tachytes and
leave to the specialists the task of adorning her with a Latin name, if it
be really the fact that the Wasp is not yet catalogued. I will be brief in
my delineation. To my thinking the best description is this: mantis-hunter.
With this information it is impossible to mistake the insect, in my
district of course. I may add that it is black, with the first two
abdominal segments, the legs and the tarsi a rusty red. Clad in the same
livery and much smaller than the female, the male is remarkable for his
eyes, which are of a beautiful lemon-yellow when he is alive. The length is
nearly half an inch for the female and a little more than half this for the
male.--Author's Note.) I do not think that she is very widely distributed.
I made her acquaintance in the Serignan woods, where she inhabits, or
rather used to inhabit--for I fear that I have depopulated and even
destroyed the community by my repeated excavations--where she used to
inhabit one of those little mounds of sand which the wind heaps up against
the rosemary clumps. Outside this small community, I never saw her again.
Her history, rich in incident, will be given with all the detail which it
deserves. I will confine myself for the moment to mentioning her rations,
which consist of Mantis-larvae, those of the Praying Mantis predominating.
(Cf. "The Life of the Grasshopper": chapters 6 to 9.--Translator's Note.)
My lists record from three to sixteen heads for each cell. Once again we
note a great inequality of rations, the reason for which we must try to
discover.

What shall I say of the Black Tachytes (T. nigra, VAN DER LIND) that I have
not already said in telling the story of the Yellow-winged Sphex? ("The
Hunting Wasps": chapters 4 to 6.--Translator's Note.) I have there
described her contests with the Sphex, whose burrow she seems to me to have
usurped; I show her dragging along the ruts in the roads a paralysed
Cricket, seized by the hauling-ropes, his antennae; I speak of her
hesitations, which lead me to suspect her for a homeless vagabond, and
finally on her surrender of her game, with which she seems at once
satisfied and embarrassed. Save for the dispute with the Sphex, an unique
event in my records as observer, I have seen all the rest many a time, but
never anything more. The Black Tachytes, though the most frequent of all in
my neighbourhood, remains a riddle to me. I know nothing of her dwelling,
her larvae, her cocoons, her family-arrangements. All that I can affirm,
judging by the invariable nature of the prey which one sees her dragging
along, is that she must feed her larvae on the same non-adult Cricket that
the Yellow-winged Sphex chooses for hers.

Is she a poacher, a pillager of other's property, or a genuine huntress? My
suspicions are persistent, though I know how chary a man should be of
suspicions. At one time I had my doubts about Panzer's Tachytes, whom I
grudged a prey to which the White-banded Sphex might have laid claim. To-
day I have no such doubts: she is an honest worker and her game is really
the result of her hunting. While waiting for the truth to be revealed and
my suspicions set aside, I will complete the little that I know of her by
noting that the Black Tachytes passes the winter in the adult form and away
from her cell. She hibernates, like the Hairy Ammophila. In warm, sheltered
places, with low, perpendicular, bare banks, dear to the Wasps, I am
certain of finding her at any time during the winter, however briefly I
investigate the earthen surface, riddled with galleries. I find the
Tachytes cowering singly in the hot oven formed by the end of a tunnel. If
the temperature be mild and the sky clear, she emerges from her retreat in
January and February and comes to the surface of the bank to see whether
spring is making progress. When the shadows fall and the heat decreases,
she reenters her winter-quarters.

The Anathema Tachytes (T. anathema, VAN DER LIND), the giant of her race,
almost as large as the Languedocian Sphex and, like her, decorated with a
red scarf round the base of the abdomen, is rarer than any of her
congeners. I have come upon her only some four or five times, as an
isolated individual and always in circumstances which will tell us of the
nature of her game with a probability that comes very near to certainty.
She hunts underground, like the Scoliae. In September I see her go down
into the soil, which has been loosened by a recent light shower; the
movement of the earth turned over keeps me informed of her subterranean
progress. She is like the Mole, ploughing through a meadow in pursuit of
his White Worm. She comes out farther on, nearly a yard from the spot at
which she went in. This long journey underground has taken her only a few
minutes.

Is this due to extraordinary powers of excavation on her part? By no means:
the Anathema Tachytes is an energetic tunneller, no doubt, but, after all,
is incapable of performing so great a labour in so short a time. If the
underground worker is so swift in her progress, it is because the track
followed has already been covered by another. The trail is ready prepared.
We will describe it, for it is clearly defined before the intervention of
the Wasp.

On the surface of the ground, for a length of two paces at most, runs a
sinuous line, a beading of crumbled soil, roughly the width of my finger.
>From this line of ramifications (others) shoot out to left and right, much
shorter and irregularly distributed. One need not be a great entomological
scholar to recognize, at the first glance, in these pads of raised earth,
the trail of a Mole-cricket, the Mole among insects. It is the Mole-cricket
who, seeking for a root to suit her, has excavated the winding tunnel, with
investigation-galleries grafted to either side of the main road. The
passage is free therefore, or at most blocked by a few landslips, of which
the Tachytes will easily dispose. This explains her rapid journey
underground.

But what does she do there? For she is always there, in the few
observations which chance affords me. A subterranean excursion would not
attract the Wasp if it had no object. And its object is certainly the
search for some sort of game for her larvae. The inference becomes
inevitable: the Anathema Tachytes, who explores the Mole-cricket's
galleries, gives her larvae this same Mole-cricket as their food. Very
probably the specimen selected is a young one, for the adult insect would
be too big. Besides, to this consideration of quantity is added that of
quality. Young and tender flesh is highly appreciated, as witness the
Tarsal Tachytes, the Black Tachytes and the Mantis-killing Tachytes, who
all three select game that is not yet made tough by age. It goes without
saying that the moment the huntress emerged from the ground I proceeded to
dig up the track. The Mole-cricket was no longer there. The Tachytes had
come too late; and so had I.

Well, how right was I to define the Tachytes as a Locust lover! What
constancy in the gastronomic rules of the race! And what tact in varying
the game, while keeping within the order of the Orthoptera! What have the
Locust, the Cricket, the Praying Mantis and the Mole-cricket in common, as
regards their general appearance? Why, absolutely nothing! None of us, if
he were unfamiliar with the delicate associations dictated by anatomy,
would think of classing them together. The Tachytes, on the other hand,
makes no mistake. Guided by her instinct, which rivals the science of a
Latreille, she groups them all together. (Pierre Andre Latreille (1762-
1833), one of the founders of entomological science, a professor at the
Musee d'histoire naturelle and member of the Academie des sciences.--
Translator's Note.)

This instinctive taxonomy becomes more surprising still if we consider the
variety of the game stored in a single burrow. The Mantis-killing Tachytes,
for instance, preys indiscriminately upon all the Mantides that occur in
her neighbourhood. I see her warehousing three of them, the only varieties,
in fact, that I know in my district. They are the following: the Praying
Mantis (M. religiosa, LIN.), the Grey Mantis (Ameles decolor, CHARP. (Cf.
"The Life of the Grasshopper": chapter 10.--Translator's Note.)) and the
Empusa (E. pauperata, LATR. (Cf. idem: chapter 9.--Translator's Note.)).
The numerical predominance in the Tachytes' cells belongs to the Praying
Mantis; and the Grey Mantis occupies second place. The Empusa, who is
comparatively rare on the brushwood in the neighbourhood, is also rare in
the store-houses of the Wasp; nevertheless her presence is repeated often
enough to show that the huntress appreciates the value of this prey when
she comes across it. The three sorts of game are in the larval state, with
rudimentary wings. Their dimensions, which vary a good deal, fluctuate
between two-fifths and four-fifths of an inch in length.

The Praying Mantis is a bright green; she boasts an elongated prothorax and
an alert gait. The other Mantis is ash-grey. Her prothorax is short and her
movements heavy. The coloration therefore is no guide to the huntress, any
more than the gait. The green and the grey, the swift and the slow are
unable to baffle her perspicacity. To her, despite the great difference in
appearance, the two victims are Mantes. And she is right.

But what are we to say of the Empusa? The insect world, at all events in
our parts, contains no more fantastic creature. The children here, who are
remarkable for finding names which really depict the animal, call the larva
"the Devilkin." It is indeed a spectre, a diabolical phantom worthy of the
pencil of a Callot. (Jacques Callot (1592-1635), the French engraver and
painter, famous for the grotesque nature of his subjects.--Translator's
Note.) There is nothing to beat it in the extravagant medley of figures in
his "Temptation of Saint Anthony." Its flat abdomen, scalloped at the
edges, rises into a twisted crook; its peaked head carries on the top two
large, divergent, tusk-shaped horns; its sharp, pointed face, which can
turn and look to either side, would fit the wily purpose of some
Mephistopheles; its long legs have cleaver-like appendages at the joints,
similar to the arm-pieces which the knights of old used to bear upon their
elbows. Perched high upon the shanks of its four hind-legs, with its
abdomen curled, its thorax raised erect, its front-legs, the traps and
implements of warfare, folded against its chest, it sways limply from side
to side, on the tip of the bough.

Any one seeing it for the first time in its grotesque pose will give a
start of surprise. The Tachytes knows no such alarm. If she catches sight
of it, she seizes it by the neck and stabs it. It will be a treat for her
children. How does she manage to recognize in this spectre the near
relation of the Praying Mantis? When frequent hunting-expeditions have
familiarized her with the last-named and suddenly, in the midst of the
chase, she encounters the Devilkin, how does she become aware that this
strange find makes yet another excellent addition to her larder? This
question, I fear, will never receive an adequate reply. Other huntresses
have already set us the problem; others will set it to us again. I shall
return to it, not to solve it, but to show even more plainly how obscure
and profound it is. But we will first complete the story of the Mantis-
killing Tachytes.

The colony which forms the subject of my investigations is established in a
mound of fine sand which I myself cut into, a couple of years ago, in order
to unearth a few Bembex larvae. The entrances to the Tachytes' dwelling
open upon the little upright bank of the section. At the beginning of July
the work is in full swing. It must have been going on already for a week or
two, for I find very forward larvae, as well as recent cocoons. There are
here, digging into the sand or returning from expeditions with their booty,
some hundred females, whose burrows, all very close to one another, cover
an area of barely a square yard. This hamlet, small in extent, but
nevertheless densely populated, shows us the Mantis-slayer under a moral
aspect which is not shared by the Locust slayer, Panzer's Tachytes, who
resembles her so closely in costume. Though engaged in individual tasks,
the first seeks the society of her kind, as do certain of the Sphex-wasps,
while the second establishes herself in solitude, after the fashion of the
Ammophila. Neither the personal form nor the nature of the occupation
determines sociability.

Crouching voluptuously in the sun, on the sand at the foot of the bank, the
males lie waiting for the females, to plague them as they pass. They are
ardent lovers, but cut a poor figure. Their linear dimensions are barely
half those of the other sex, which implies a volume only one-eighth as
great. At a short distance they appear to wear on their heads a sort of
gaudy turban. At close quarters this headgear is seen to consist of the
eyes, which are very large and a bright lemon-yellow and which almost
entirely surround the head.

At ten o'clock in the morning, when the heat begins to grow intolerable to
the observer, there is a continual coming and going between the burrows and
the tufts of grass, everlasting, thyme and wormwood, which constitute the
Tachytes' hunting-grounds within a moderate radius. The journey is so short
that the Wasp brings her game home on the wing, usually in a single flight.
She holds it by the fore-part, a very judicious precaution, which is
favourable to rapid stowage in the warehouse, for then the Mantis' legs
stretch backwards, along the axis of the body, instead of folding and
projecting sideways, when their resistance would be difficult to overcome
in a narrow gallery. The lanky prey dangles beneath the huntress, all limp,
lifeless and paralysed. The Tachytes, still flying, alights on the
threshold of the home and immediately, contrary to the custom of Panzer's
Tachytes, enters with her prey trailing behind her. It is not unusual for a
male to come upon the scene at the moment of the mother's arrival. He is
promptly snubbed. This is the time for work, not for amusement. The
rebuffed male resumes his post as a watcher in the sun; and the housewife
stows her provisions.

But she does not always do so without hindrance. Let me recount one of the
misadventures of this work of storage. There is in the neighbourhood of the
burrows a plant which catches insects with glue. It is the Oporto silene
(S. portensis), a curious growth, a lover of the sea-side dunes, which,
though of Portuguese origin, as its name would seem to indicate, ventures
inland, even as far as my part of the country, where it represents perhaps
a survivor of the coastal flora of what was once a Pliocene sea. The sea
has disappeared; a few plants of its shores have remained behind. This
Silene carries in most of its internodes, in those both of the branches and
of the main stalk, a viscous ring, two- to four-fifths of an inch wide,
sharply delimited above and below. The coating of glue is of a pale brown.
Its stickiness is so great that the least touch is enough to hold the
object. I find Midges, Plant-lice and Ants caught in it, as well as tufted
seeds which have blown from the capitula of the Cichoriaceae. A Gad-fly, as
big as a Blue bottle, falls into the trap before my eyes. She has barely
alighted on the perilous perch when lo, she is held by the hinder tarsi!
The Fly makes violent efforts to take wing; she shakes the slender plant
from top to bottom. If she frees her hinder tarsi she remains snared by the
front tarsi and has to begin all over again. I was doubting the possibility
of her escape when, after a good quarter of an hour's struggle, she
succeeded in extricating herself.

But, where the Gad-fly has got off, the Midge remains. The winged Aphis
also remains, the Ant, the Mosquito and many another of the smaller
insects. What does the plant do with its captures? Of what use are these
trophies of corpses hanging by a leg or a wing? Does the vegetable bird-
limer, with its sticky rings, derive advantage from these death-struggles?
A Darwinian, remembering the carnivorous plants, would say yes. As for me,
I don't believe a word of it. The Oporto silene is ringed with bands of
gum. Why? I don't know. Insects are caught in these snares. Of what use are
they to the plant? Why, none at all; and that's all about it. I leave to
others, bolder than myself, the fantastic idea of taking these annular
exudations for a digestive fluid which will reduce the captured Midges to
soup and make them serve to feed the Silene. Only I warn them that the
insects sticking to the plant do not dissolve into broth, but shrivel,
quite uselessly, in the sun.

Let us return to the Tachytes, who is also a victim of the vegetable snare.
With a sudden flight, a huntress arrives, carrying her drooping prey. She
grazes the Silene's lime-twigs too closely. Behold the Mantis caught by the
abdomen. For twenty minutes at least the Wasp, still on the wing, tugs at
her, tugging again and again, to overcome the cause of the hitch and
release the spoil. The hauling-method, a continuation of the flight, comes
to nothing; and no other is attempted. At last the insect wearies and
leaves the Mantis hanging to the Silene.

Now or never was the moment for the intervention of that tiny glimmer of
reason which Darwin so generously grants to animals. Do not, if you please,
confound reason with intelligence, as people are too prone to do. I deny
the one; and the other is incontestable, within very modest limits. It was,
I said, the moment to reason a little, to discover the cause of the hitch
and to attack the difficulty at its source. For the Tachytes the matter was
of the simplest. She had but to grab the body by the skin of the abdomen
immediately above the spot caught by the glue and to pull it towards her,
instead of persevering in her flight without releasing the neck. Simple
though this mechanical problem was, the insect was unable to solve it,
because she was not able to trace the effect back to the cause, because she
did not even suspect that the stoppage had a cause.

Ants doting on sugar and accustomed to cross a foot-bridge in order to
reach the warehouse are absolutely prevented from doing so when the bridge
is interrupted by a slight gap. They would only need a few grains of sand
to fill the void and restore the causeway. They do not for a moment dream
of it, plucky navvies though they be, capable of raising miniature
mountains of excavated soil. We can get them to give us an enormous cone of
earth, an instinctive piece of work, but we shall never obtain the
juxtaposition of three grains of sand, a reasoned piece of work. The Ant
does not reason, any more than the Tachytes.

If you bring up a tame Fox and set his platter of food before him, this
creature of a thousand tricks confines himself to tugging with all his
might at the leash which keeps him a step or two from his dinner. He pulls
as the Tachytes pulls, exhausts himself in futile efforts and then lies
down, with his little eyes leering fixedly at the dish. Why does he not
turn round? This would increase his radius; and he could reach then the
food with his hind-foot and pull it towards him. The idea never occurs to
him. Yet another animal deprived of reason.

Friend Bull, my Dog, is no better-endowed, despite his quality as a
candidate for humanity. In our excursions through the woods, he happens to
get caught by the paw in a wire snare set for rabbits. Like the Tachytes,
he tugs at it obstinately and only pulls the noose tighter. I have to
release him when he does not himself succeed in snapping the wire by his
hard pulling. When he tries to leave the room, if the two leaves of the
door are just ajar, he contents himself with pushing his muzzle, like a
wedge, into the too narrow aperture. He moves forward, pushing in the
direction which he wishes to take. His simple, dog-like method has one
unfailing result: the two leaves of the door, when pushed, merely shut
still closer. It would be easy for him to pull one of them towards him with
his paw, which would make the passage wider; but this would be a movement
backward, contrary to his natural impulse; and so he does not think of it.
Yet another creature that does not reason.

The Tachytes, who stubbornly persists in tugging at her limed Mantis and
refuses to acknowledge any other method of wresting her from the Silene's
snare, shows us the Wasp in an unflattering light. What a very poor
intellect! The insect becomes only the more wonderful, therefore, when we
consider its supreme talent as an anatomist. Many a time I have insisted
upon the incomprehensible wisdom of instinct; I do so again at the risk of
repeating myself. An idea is like a nail: it is not to be driven in save by
repeated blows. By hitting it again and again, I hope to make it enter the
most rebellious brains. This time I shall attack the problem from the other
end, that is, I shall first allow human knowledge to have its say and shall
then interrogate the insect's knowledge.

The outward structure of the Praying Mantis would of itself be enough to
teach us the arrangement of the nerve-centres which the Tachytes has to
injure in order to paralyse its victim, which is destined to be devoured
alive but harmless. A narrow and very long prothorax divides the front pair
of legs from the two hinder pairs. There must therefore be an isolated
ganglion in front and two ganglia, close to each other, about two-fifths of
an inch back. Dissection confirms this forecast completely. It shows us
three fairly bulky thoracic ganglia, arranged in the same manner as the
legs. The first which actuates the fore-legs, is placed opposite their
roots. It is the largest of the three. It is also the most important, for
it presides over the insect's weapons, over the two powerful arms, toothed
like saws and ending in harpoons. The other two, divided from the first by
the whole length of the prothorax, each face the origin of the
corresponding legs; consequently they are very near each other. Beyond them
are the abdominal ganglia, which I pass over in silence, as the operating
insect does not have to trouble about them. The movements of the belly are
mere pulsations and are in no way dangerous.

Now let us do a little reasoning on behalf of our non-reasoning insect. The
sacrificer is weak; the victim is comparatively powerful. Three strokes of
the lancet must abolish all offensive movement. Where will the first stroke
be delivered? In front is a real engine of warfare, a pair of powerful
shears with toothed jaws. Let the fore-arm close upon the upper arm; and
the imprudent insect, crushed between the two saw-blades, will be torn to
pieces; wounded by the terminal hook, it will be eviscerated. This
ferocious mechanism is the great danger; it is this that must be mastered
at the outset, at the risk of life; the rest is less urgent. The first blow
of the stylet, cautiously directed, is therefore aimed at the lethal fore-
legs, which imperil the vivisector's own existence. Above all, there must
be no hesitation. The blow must be accurate then and there, or the
sacrificer will be caught in the vice and perish. The two other pairs of
legs present no danger to the operator, who might neglect them if she had
only her own security to think of; but the surgeon is operating with a view
to the egg, which demands complete immobility in the provisions. Their
centres of innervation will therefore be stabbed as well, with the leisure
which the Mantis, now put out of action, permits. These legs, as well as
their nervous centres, are situated very far behind the first point
attacked. There is a long neutral interval, that of the prothorax, into
which it is quite useless to drive the sting. This interval has to be
crossed; by a backward movement conforming with the secrets of the victim's
internal anatomy, the second ganglion must be reached and then its
neighbour, the third. In short, the surgical operation may be formulated
thus: a first stab of the lancet in front; a considerable movement to the
rear, measuring about two-fifths of an inch; lastly, two lancet-thrusts at
two points very close together. Thus speaks the science of man; thus
counsels reason, guided by anatomical structure. Having said this much let
us observe the insect's practice.

There is no difficulty about seeing the Tachytes operate in our presence;
we have only to resort to the method of substitution, which has already
done me so much service, that is, to deprive the huntress of her prey and
at once to give her, in exchange, a living Mantis of about the same size.
This substitution is impracticable with the majority of the Tachytes, who
reach the threshold of their dwelling in a single flight and at once vanish
underground with their game. A few of them, from time to time, harassed
perhaps by their burden, chance to alight at a short distance from their
burrow, or even drop their prey. I profit by these rare occasions to
witness the tragedy.

The dispossessed Wasp recognizes instantly, from the proud bearing of the
substituted Mantis, that she is no longer embracing and carrying off an
inoffensive carcase. Her hovering, hitherto silent, develops a buzz,
perhaps to overawe the victim; her flight becomes an extremely rapid
oscillation, always behind the quarry. It is as who should say the quick
movement of a pendulum swinging without a wire to hang from. The Mantis,
however, lifts herself boldly upon her four hind-legs; she raises the fore-
part of her body, opens, closes and again opens her shears and presents
them threateningly at the enemy; using a privilege which no other insect
shares, she turns her head this way and that, as we do when we look over
our shoulders; she faces her assailant, ready to strike a return blow
wheresoever the attack may come. It is the first time that I have witnessed
such defensive daring. What will be the outcome of it all?

The Wasp continues to oscillate behind the Mantis, in order to avoid the
formidable grappling-engine; then, suddenly, when she judges that the other
is baffled by the rapidity of her manoeuvres, she hurls herself upon the
insect's back, seizes its neck with her mandibles, winds her legs round its
thorax and hastily delivers a first thrust of the sting, to the front, at
the root of the lethal legs. Complete success! The deadly shears fall
powerless. The operator then lets herself slip as she might slide down a
pole, retreats along the Mantis' back and, going a trifle lower, less than
a finger's breadth, she stops and paralyses, this time without hurrying
herself, the two pairs of hind-legs. It is done: the patient lies
motionless; only the tarsi quiver, twitching in their last convulsions. The
sacrificer brushes her wings for a moment and polishes her antennae by
passing them through her mouth, an habitual sign of tranquillity returning
after the emotions of the conflict; she seizes the game by the neck, takes
it in her legs and flies away with it.

What do you say to it all? Do not the scientist's theory and the insect's
practice agree most admirably? Has not the animal accomplished to
perfection what anatomy and physiology enabled us to foretell? Instinct, a
gratuitous attribute, an unconscious inspiration, rivals knowledge, that
most costly acquisition. What strikes me most is the sudden recoil after
the first thrust of the sting. The Hairy Ammophila, operating on her
caterpillar, likewise recoils, but progressively, from one segment to the
next. Her deliberate surgery might receive a quasi-explanation if we
ascribe it to a certain uniformity. With the Tachytes and the Mantis this
paltry argument escapes us. Here are no lancet-pricks regularly
distributed; on the contrary, the operating-method betrays a lack of
symmetry which would be inconceivable, if the organization of the patient
did not serve as a guide. The Tachytes therefore knows where her prey's
nerve-centres lie; or, to speak more correctly, she behaves as though she
knew.

This science which is unconscious of itself has not been acquired, by her
and by her race, through experiments perfected from age to age and habits
transmitted from one generation to the next. It is impossible, I am
prepared to declare a hundred times, a thousand times over, it is
absolutely impossible to experiment and to learn an art when you are lost
if you do not succeed at the first attempt. Don't talk to me of atavism, of
small successes increasing by inheritance, when the novice, if he
misdirected his weapon, would be crushed in the trap of the two saws and
fall a prey to the savage Mantis! The peaceable Locust, if missed, protests
against the attack with a few kicks; the carnivorous Mantis, who is in the
habit of feasting on Wasps far more powerful than the Tachytes, would
protest by eating the bungler; the game would devour the hunter, an
excellent catch. Mantis-paralysing is a most perilous trade and admits of
no half-successes; you have to excel in it from the first, under pain of
death. No, the surgical art of the Tachytes is not an acquired art. Whence
then does it come, if not from the universal knowledge in which all things
move and have their being!

What would happen if, in exchange for her Praying Mantis, I were to give
the Tachytes a young Grasshopper? In rearing insects at home, I have
already noted that the larvae put up very well with this diet; and I am
surprised that the mother does not follow the example of the Tarsal
Tachytes and provide her family with a skewerful of Locusts instead of the
risky prey which she selects. The diet would be practically the same; and
the terrible shears would no longer be a danger. With such a patient would
her operating-method remain the same; should we again see a sudden recoil
after the first stab under the neck; or would the vivisector modify her art
in conformity with the unfamiliar nervous organization?

This second alternative is highly improbable. It would be nonsense to
expect to see the paralyser vary the number and the distribution of the
wounds according to the genus of the victim. Supremely skilled in the task
that has fallen to its lot, the insect knows nothing further.

The first alternative seems to offer a certain chance and deserves a test.
I offer the Tachytes, deprived of her Mantis, a small Grasshopper, whose
hind-legs I amputate to prevent his leaping. The disabled Acridian jogs
along the sand. The Wasp flies round him for a moment, casts a contemptuous
glance upon the cripple and withdraws without attempting action. Let the
prey offered be large or small, green or grey, short or long, rather like
the Mantis or quite different, all my efforts miscarry. The Tachytes
recognizes in an instant that this is no business of hers; this is not her
family game; she goes off without even honouring my Grasshoppers with a
peck of her mandibles.

This stubborn refusal is not due to gastronomical causes. I have stated
that the larvae reared by my own hands feed on young Grasshoppers as
readily as on young Mantes; they do not seem to perceive any difference
between the two dishes; they thrive equally on the game chosen by me and
that selected by the mother. If the mother sets no value on the
Grasshopper, what then can be the reason of her refusal? I can see only
one: this quarry, which is not hers, perhaps inspires her with fear, as any
unknown thing might do; the ferocious Mantis does not alarm her, but the
peaceable Grasshopper terrifies her. And then, if she were to overcome her
apprehensions, she does not know how to master the Acridian and, above all,
how to operate upon him. To every man his trade, to every Wasp her own way
of wielding her sting. Modify the conditions ever so slightly; and these
skilful paralysers are at an utter loss.

To every insect also its own art of fashioning the cocoon, an art which
varies greatly, an art in which the larva displays all the resources of its
instincts. The Tachytes, the Bembeces, the Stizi, the Palari and other
burrowers build composite cocoons, hard as fruit-stones, formed of an
encrustation of sand in a network of silk. We are already acquainted with
the work of the Bembex. I will recall the fact that their larva first
weaves a conical, horizontal bag of pure white silk, with wide meshes, held
in place by interlaced threads which fix it to the walls of the cell. I
have compared this bag, because of its shape, with a fishtrap. Without
leaving this hammock, stretching its neck through the orifice, the worker
gathers from without a little heap of sand, which it stores inside its
workshop. Then, selecting the grains one by one, it encrusts them all
around itself in the fabric of the bag and cements them with the fluid from
its spinnerets, which hardens at once. When this task is finished, the
house has still to be closed, for it has been wide open all this time to
permit of the renewal of the store of sand as the heap inside becomes
exhausted. For this purpose a cap of silk is woven across the opening and
finally encrusted with the materials which the larva has retained at its
disposal.

The Tachytes builds in quite another fashion, although its work, once
finished, does not differ from that of the Bembex. The larva surrounds
itself, to begin with, about the middle of its body with a silken girdle
which a number of threads, very irregularly distributed, hold in place and
connect with the walls of the cell. Sand is collected, within reach of the
worker, on this general scaffolding. Then begins the work of minor masonry,
with grains of sand for rubble and the secretion of the spinnerets for
cement. The first course is laid upon the fore-edge of the suspensory ring.
When the circle is completed, a second course of grains of sand, stuck
together by the fluid silk, is raised upon the hardened edge of what has
just been done. Thus the work proceeds, by ring-shaped courses, laid edge
to edge, until the cocoon, having acquired half of its proper length, is
rounded into a cap and finally is closed. The building-methods of the
Tachytes-larva remind me of a mason constructing a round chimney, a narrow
tower of which he occupies the centre. Turning on his own axis and using
the materials placed to his hand, he encloses himself little by little in
his sheath of masonry. In the same way the worker encloses itself in its
mosaic. To build the second half of the cocoon, the larva turns round and
builds in the same way on the other edge of the original ring. In about
thirty-six hours the solid shell is completed.

I am rather interested to see the Bembex and the Tachytes, two workers in
the same guild, employ such different methods to achieve the same result.
The first begins by weaving an eel-trap of pure silk and next encrusts the
grains of sand inside; the second, a bolder architect, is economical of the
silk envelope, confines itself to a hanging girdle and builds course by
course. The building-materials are the same: sand and silk; the
surroundings amid which the two artisans work are the same: a cell in a
soil of sandy gravel; yet each of the builders possesses its individual
art, its own plan, its one method.

The nature of the food has no more effect upon the larva's talents than the
environment in which it lives or the materials employed. The proof of this
is furnished by Stiza ruficornis, another builder of cocoons in grains of
sand cemented with silk. This sturdy Wasp digs her burrows in soft
sandstone. Like the Mantis-killing Tachytes, she hunts the various Mantides
of the countryside, consisting mainly of the Praying Mantis; only her large
size requires them to be more fully developed, without however having
attained the form and the dimensions of the adult. She places three to five
of them in each cell.

In solidity and volume her cocoon rivals that of the largest Bembex; but it
differs from it, at first sight, by a singular feature of which I know no
other example. From the side of the shell, which is uniformly smoothed on
every side, a rough knob protrudes, a little clod of sand stuck on to the
rest. The work of Stizus ruficornis can at once be recognized, among all
the other cocoons of a similar nature, by this protuberance.

Its origin will be explained by the method which the larva follows in
constructing its strong-box. At the beginning, a conical bag is woven of
pure white silk; you might take it for the initial eel-trap of the
Bembeces, only this bag has two openings, a very wide one in front and
another, very narrow one at the side. Through the front opening the Stizus
provides itself with sand as and when it spends this material on encrusting
the interior. This strengthens the cocoon; and the cap which closes it is
made next. So far it is exactly like the work of the Bembex. We now have
the worker enclosed, engaged in perfecting the inner wall. For these final
touches a little more sand is needed. It obtains it from outside by means
of the aperture which it has taken the precaution of contriving in the side
of its building, a narrow dormer-window just large enough to allow its
slender neck to pass. When the store has been taken in, this accessory
orifice, which is used only during the last few moments, is closed with a
mouthful of mortar, thrust outward from within. This forms the irregular
nipple which projects from the side of the shell.

For the present I shall not expatiate further upon Stizus ruficornis, whose
complete biography would be out of place in this chapter. I will limit
myself to mentioning its method of constructing strong-boxes in order to
compare it with that of the Bembex and above all with that of the Tachytes,
a consumer, like itself, of Praying Mantes. From this parallel it seems to
me to follow that the conditions of life in which men see to-day the origin
of instincts--the type of food, the surroundings amid which the larval life
is passed, the materials available for a defensive wrapper and other
factors which the evolutionists are accustomed to invoke--have no actual
influence upon the larva's industry. My three architects in glued sand,
even when all the conditions, down to the nature of the provisions, are the
same, adopt different means to execute an identical task. They are
engineers who have not graduated from the same school, who have not been
educated on the same principles, though the lesson of things is almost the
same for all of them. The workshop, the work, the provisions have not
determined the instinct. The instinct comes first; it lays down laws
instead of being subject to them.

CHAPTER 7. CHANGE OF DIET.

Brillat-Savarin, when pronouncing his famous maxim, "Tell me what you eat
and I will tell you what you are," certainly never suspected the signal
confirmation which the entomological world would bestow upon his saying.
Our gastrosopher was speaking only of the culinary caprices of man rendered
fastidious by the sweets of life; but he might, in a more serious
department of thought, have given his formula a wider and more general
bearing and applied it to the dishes which vary so greatly according to
latitude, climate and customs; he might above all have taken into his
reckoning the harsh realities suffered by the common people, when perhaps
his ideal of moral worth would have been found in a platter of chick-peas
oftener than in a pot of pate de foie gras. No matter: his aphorism, the
mere whimsical sally of an epicure, becomes an imperious truth if we forget
the luxury of the table and look into what is eaten by the little world
which swarms around us.

To each its mess. The cabbage Pieris consumes the pungent leaves of the
Cruciferae as the food of her infancy; the Silkworm disdains any foliage
other than that of the mulberry-tree. The Spurge Hawk-moth requires the
caustic milk-sap of the tithymals: the Corn-weevil the grain of wheat; the
Pea-weevil, the seeds of the Leguminosae; the Balaninus (A genus of Beetles
including the Acorn-weevil, the Nut-weevil and others.--Translator's Note.)
the hazel-nut, the chestnut, the acorn; the Brachycera (A division of Flies
including the Gad-flies and Robber-flies.--Translator's Note.) the clove of
garlic. Each has its diet, each its plant; and each plant has its customary
guests. Their relations are so precise that in many cases one might
determine the insect by the vegetable which supports it, or the vegetable
by the insect.

If you know the lily, you may name as a Crioceris the tiny scarlet
Scarabaeid that inhabits it and peoples its leaves with larvae which keep
themselves cool beneath an overcoat of ordure. (For the Lily-beetle, or
Crioceris merdigera, cf. "The Glow-worm and Other Beetles," by J. Henri
Fabre, translated by Alexander Teixeira de Mattos: chapters 16 and 17.--
Translator's Note.) If you know the Crioceris, you may name as a lily the
plant which she devastates. It will not perhaps be the common or white
lily, but some other representative of the same family--Turk's cap lily,
orange lily, scarlet Martagon, lancifoliate lily, tiger-spotted lily,
golden lily--hailing from the Alps or the Pyrenees, or brought from China
or Japan. Relying on the Crioceris, who is an expert judge of exotic as
well as of native Liliaceae, you may name as a lily the plant with which
you are unacquainted and trust the word of this singular botanical master.
Whether the flower be red, yellow, ruddy-brown or sown with crimson spots,
characteristics so unlike the immaculate whiteness of the familiar flower,
do not hesitate, adopt the name dictated by the Beetle. Where man is liable
to mistake the insect is never mistaken.

This insect botany, a cause of such grievous tribulations, has always
impressed the worker in the fields, who for all that, is a very indifferent
observer. The man who was the first to see his cabbage-plot devastated by
caterpillars made the acquaintance of the Pieris. Science completed the
process, in its desire to serve a useful purpose or merely to seek truth
for truth's sake; and to-day the relations between the insect and the plant
form a collection of records as important from the philosophical as from
the practical, agricultural point of view. What is much less familiar to
us, because it touches us less nearly, is the zoology of the insect, that
is to say, the selection which it makes, to feed its larva, of this or that
animal species, to the exclusion of others. The subject is so vast that a
volume were not sufficient to exhaust it; besides, data are lacking in the
vast majority of cases. It is reserved for a still very distant future to
raise this point of biology to the level already reached by the question of
vegetable diet. It will be enough if I contribute a few observations
scattered through my writings or my notes.

What does the Wasp addicted to a predatory life eat, of course in the
larval state? Now, to begin with, we see natural sections which adopt as
their prey different species of one and the same order, in one and the same
group. Thus the Ammophilae hunt exclusively the larvae of the night-flying
Moths. This taste is shared by the Eumenes, a very different genus. (Cf.
"The Mason-wasps" by J. Henri Fabre, translated by Alexander Teixeira de
Mattos: chapter 1.--Translator's Note.) The Spheges and Tachytes are
addicted to Orthoptera; the Cerceres, apart from a few exceptions, are
faithful to the Weevil; both the Philanthi and the Palari capture only
Hymenoptera; the Pompili specialize in hunting the Spider; the Astata
revels in the flavour of Bugs; the Bembeces want Flies and nothing else;
the Scoliae enjoy the monopoly of the Lamellicorn-grubs; the Pelopaei
favour the young Epeirae (Or Garden Spiders. Cf. "The Life of the Spider":
chapters 9 to 14 and appendix.--Translator's Note.), the Stizi vary in
opinion: of the two in my neighbourhood, one, S. ruficornis, fills her
larder with Mantes and the other, S. tridentatus, fills it with Cicadellae
(Cf. "The Life of the Grasshopper": chapter 20.--Translator's Note.);
lastly, the Crabronidae (Any Flies akin to the House-fly.--Translator's
Note.). levy tribute upon the rabble of the Muscidae. (Hornets.--
Translator's Note.)

Already you see what a magnificent classification of these game-hunters
might be made with a faithfully listed bill of fare. Natural groups stand
out, characterized merely by the identity of their victuals. I trust that
the methodical science of the future will take account of these gastronomic
laws, to the great relief of the entomological novice, who is too often
hampered by the snares of the mouth-parts, the antennae and the nervures of
the wings. I call for a classification in which the insect's aptitudes, its
diet, its industry and its habits shall take precedence of the shape of a
joint in its antennae. It will come; but when?

If from generalities we descend to details, we shall see that the very
species may, in many instances, be determined from the nature of its
victuals. The number of burrows of Philanthus apivorus which I have
inspected since I have been rummaging the hot roadside embankments, to
enquire into their population, would seem hyperbolical were I able to state
the figures. (For the Bee-eating Philanthus cf. Chapter 10 of the present
volume.--Translator's Note.) They must amount, it seems to me, to
thousands. Well, in this multitude of food-stores, whether recent or
ancient, uncovered for a purpose or encountered by chance, I have not once,
not as often as once, discovered other remains than those of the Hive-bee:
the imperishable wings, still connected in pairs, the cranium and thorax
enveloped in a violet shroud, the winding-sheet which time throws over
these relics. To-day as when I was a beginner, ever so long ago; in the
north as in the south of the country which I explored; in mountainous
regions as on the plains, the Philanthus follows an unvarying diet: she
must have the Hive-bee, always the Bee and never any other, however closely
various other kinds of game resemble the Bee in quality. If, therefore,
when exploring sunny banks, you find beneath the soil a small parcel of
mutilated Bees, that will be enough to point to the existence of a local
colony of Philanthus apivorus. She alone knows the recipe for making potted
Bee-meat. The Crioceris was but now teaching us all about the lily family;
and here the mildewed body of the Bee tells us of the Philanthus and her
lair.

Similarly the female Ephippiger helps us to identify the Languedocian
Sphex: her relics, the cymbals and the long sabre, are the unmistakable
sign of the cocoon to which they adhere. The black Cricket, with his red-
braided thighs, is the infallible label of the Yellow-winged Sphex; the
larva of Oryctes nasicornis tells us of the Garden Scolia as certainly as
the best description; the Cetonia-grub proclaims the Two-banded Scolia and
the larva of the Anoxia announces the Interrupted Scolia.

After these exclusive ones, who disdain to vary their meals, let us mention
the eclectics, who, in a group which is generally well-defined, are able to
select among different kinds of game appropriate to their bulk. The Great
Cerceris (Cerceris tuberculata. Cf. "The Hunting Wasps": chapters 2 and 3.-
-Translator's Note.) favours above all Cleonus ophthalmicus, one of the
largest of our Weevils; but at need she accepts the other Cleoni, as well
as the kindred genera, provided that the capture be of an imposing size.
Cerceris arenaria (Cf. idem: chapter 1.--Translator's Note.) extends her
hunting-grounds farther afield: any Weevil of average dimensions is to her
a welcome capture. The Buprestis-hunting Cerceris adopts all the Buprestes
indiscriminately, so long as they are not beyond her strength. The Crowned
Philanthus (P. coronatus, FAB.) fills her underground warehouses with
Halicti chosen among the biggest. (Cf. "Bramble-bees and Others" by J.
Henri Fabre, translated by Alexander Teixeira de Mattos: chapters 12 to
14.--Translator's Note.) Much smaller than her kinswoman, Philanthus
raptor, LEP., stores away Halicti chosen among the less large species. Any
adult Acridian approaching an inch in length suits the White-banded Sphex.
The various tidae of the neighbourhood are admitted to the larder of Stizus
ruficornis and of the Mantis-hunting Tachytes on the sole condition of
being young and tender. The largest of our Bembeces (B. rostrata, FAB., and
B. bidentata, VAN DER LIND (For the Rostrate Bembex and the Two-pronged
Bembex, cf. "The Hunting Wasps": chapter 14.--Translator's Note.)) are
eager consumers of Gad-flies. With these chief dishes they associate
relishes levied indifferently from the rest of the Fly clan. The Sandy
Ammophila (A. sabulosa, VAN DER LIND (Cf. idem: chapter 13.--Translator's
Note.)) and the Hairy Ammophila (A. hirsuta, KIRB.) cram into each burrow a
single but corpulent caterpillar, always of the Moth tribe and varying
greatly in coloration, which denotes distinct species. The Silky Ammophila
(A. holosericea, VAN DER LIND. (Cf. idem: chapter 14.--Translator's Note.))
has a better assorted diet. She requires for each banqueter three or four
items, which include the Measuring-worms, or Loopers, and the caterpillars
of ordinary Moths, all of which are equally appreciated. The Brown-winged
Solenius (S. fascipennis, LEP.), who elects to dwell in the soft dead wood
of old willow-trees, has a marked preference for Virgil's Bee, Eristalis
tenax (Actually the Common Drone-fly and somewhat resembling a Bee in
appearance. Cf. "The Hunting Wasps": chapter 14.--Translator's Note.),
willingly adding, sometimes as a side-dish, sometimes as the principal
game, Helophilus pendulus, whose costume is very different. On the faith of
indistinguishable remains, we must no doubt enter a number of other Flies
in her game-book. The Golden-mouthed Hornet (Crabro chrysostomus, LEP.)
another burrower in old willow-trees, prefers the Syrphi, without
distinction of species. (The Syrphi, like the Eristales, resemble Bees
through having the abdomen transversely banded with yellow.--Translator's
Note.) The Wandering Solenius (S. vagus, LEP. (For this Fly-hunting insect
cf. "Bramble-bees and Others": chapters 1 and 3.--Translator's Note.)), an
inmate of the dry bramble-stems and of the dwarf-elder, lays under
contribution for her larder the genera Syritta, Sphaerophoria, Sarcophaga,
Syrphus, Melanophora, Paragus and apparently many others. The species which
recurs most frequently in my notes is Syritta pipiens.

Without pursuing this tedious list any farther, we plainly perceive the
general result. Each huntress has her characteristic tastes, so much so
that, when we know the bill of fare, we can tell the genus and very often
the species of the guest, thus proving the proud truth of the maxim, "Tell
me what you eat and I will tell you what you are."

There are some which always need the same prey. The offspring of the
Languedocian Sphex religiously consume the Ephippiger, that family dish so
dear to their ancestors and no less dear to their descendants; no
innovation in the ancient usages can tempt them. Others are better suited
by variety, for reasons connected with flavour or with facility of supply;
but then the selection of the game is kept within fixed limits. A natural
group, a genus, a family, more rarely almost a whole order: this is the
hunting-ground beyond which poaching is strictly forbidden. The law is
absolute; and one and all scrupulously refrain from transgressing it.

In the place of the Praying Mantis, offer the Mantis-hunting Tachytes an
equivalent in the shape of a Locust. She will scorn the morsel, though it
would seem to be of excellent flavour, seeing that Panzer's Tachytes
prefers it to any other form of game. Offer her a young Empusa, who differs
so widely from the Mantis in shape and colour: she will accept without
hesitation and operate before your eyes. Despite its fantastic appearance,
the Devilkin is instantly recognized by the Tachytes as a Mantid and
therefore as game falling within her scope.

In exchange for her Cleonus, give to the Great Cerceris a Buprestis, the
delight of one of her near kinsfolk. She will have nothing to say to the
sumptuous dish. Accept that! She, a Weevil-eater! Never in this world!
Present her with a Cleonus of a different species, or any other large
Weevil, of a sort which she has most probably never seen before, since it
does not figure on the inventory of the provisions in her burrows. This
time there is no show of disdain: the victim is seized and stabbed in the
regulation manner and forthwith stored away.

Try to persuade the Hairy Ammophila that Spiders have a nutty flavour, as
Lalande asserts; and you will see how coldly your hints are received.
(Joseph Jerome Le Francois de Lalande (1732-1807), the astronomer. Even
after he had achieved his reputation, he sought means, outside the domain
of science, to make himself talked about and found these in the display
partly of odd tastes, such as that for eating Spiders and caterpillars, and
partly of atheistical opinions.--Translator's Note.) Try merely to convince
her that the caterpillar of a Butterfly is as good to eat as the
caterpillar of a Moth. You will not succeed. But, if you substitute for her
underground larva, which I suppose to be grey, another underground larva
striped with black, yellow, rusty-red or any other tint, this change of
coloration will not prevent her from recognizing, in the substituted dish,
a victim to her liking, an equivalent of her Grey Worm.

So with the rest, so far as I have been able to experiment with them. Each
obstinately refuses what is alien to her hunting-preserves, each accepts
whatever belongs to them, always provided that the game substituted is much
the same in size and development as that whereof the owner has been
deprived. Thus the Tarsal Tachytes, an appreciative epicure of tender
flesh, would not consent to replace her pinch of young Acridian-grubs with
the one big Locust that forms the food of Panzer's Tachytes; and the
latter, in her turn, would never exchange her adult Acridian for the
other's menu of small fry. The genus and the species are the same, but the
age differs; and this is enough to decide the question of acceptance or
refusal.

When its depredations cover a somewhat extensive group, how does the insect
manage to recognize the genera, the species composing her allotted portion
and to distinguish them from the rest with an assured vision which the
inventory of her burrows proves never to be at fault? Is it the general
appearance that guides her? No, for in some Bembex-burrows we shall find
Sphaerophoriae, those slender, thong-like creatures, and Bombylii, looking
like velvet pincushions; no again, for in the pits of the Silky Ammophila
we shall see, side by side, the caterpillar of the ordinary shape and the
Measuring-worm, a living pair of compasses which progresses by alternately
opening out and closing; no, once more, for in the storerooms of Stizus
ruficornis and the Mantis-hunting Tachytes we see stacked beside the Mantis
the Empusa, her unrecognizable caricature.

Is it the colouring? Not at all. There is no lack of instances. What a
variety of hues and metallic reflections, distributed in a host of
different fashions, appear in the Buprestes that are hunted by the Cerceris
celebrated by Leon Dufour. (Jean Marie Leon Dufour (1780-1865) was an army
surgeon who served with distinction in several campaigns and subsequently
practised as a doctor in the Landes. He attained great eminence as a
naturalist. Cf. "The Hunting Wasps": chapter 1; also "The Life of the
Spider": chapter 1.--Translator's Note.) A painter's palette, containing
crushed gold, bronze, ruby and amethyst, would find it difficult to rival
these sumptuous colours. Nevertheless the Cerceris makes no mistake: all
this nation of insects, so indifferently attired, represents to her, as to
the entomologist, the nation of the Buprestes. The inventory of the
Hornet's larder will include Diptera clad in grey or russet frieze; others
are girdled with yellow, flecked with white, adorned with crimson lines;
others are steel-blue, ebony black, or coppery green; and underneath this
variety of dissimilar costumes we find the invariable Fly.

Let us take a concrete example. Ferrero's Cerceris (C. Ferreri, VAN DER
LIND) consumes Weevils. Her burrows are usually lined with Phynotomi and
Sitones both an indeterminate grey, and Otiorhynchi, black or tan-coloured.
Now I have sometimes happened to unearth from her cells a collection of
veritable jewels which, thanks to their bright metallic lustre, made a most
striking contrast with the sombre Otiorhynchus. These were the Rhynchites
(R. betuleti), who roll the vine-leaves into cigars. Equally magnificent,
some of them were azure blue, others copper gilt, for the cigar-roller has
a twofold colouring. How did the Cerceris manage to recognize in these
jewels the Weevil, the near relative of the vulgar Phynotomus? Any such
encounters probably found her lacking in expert knowledge; her race cannot
have handed down to her other than very indeterminate propensities, for she
does not appear to make frequent use of the Rhynchites, as is proved by my
infrequent discovery of them amid the mass of my numerous excavations. For
the first time, perhaps, passing through a vineyard, she saw the rich
Beetle gleaming on a leaf; it was not for her a dish in current
consumption, consecrated by the ancient usages of the family. It was
something novel, exceptional, extraordinary. Well, this extraordinary
creature is recognized with certainty as a Weevil and stored away as such.
The glittering cuirass of the Rhynchites goes to take its place beside the
grey cloak of the Phynotomus. No, it is not the colour that guides the
choice.

Neither is it the shape. Cerceris arenaria hunts any medium-sized Weevil. I
should be putting the reader's patience to too great a test if I attempted
to give in this place a complete inventory of the specimens identified in
her larder. I will mention only two, which my latest searches around my
village have revealed. The Wasp goes hunting on the holm-oaks of the
neighbouring hills the Pubescent Brachyderes (B. pubescens) and the Acorn-
weevil (Balaninus glandium). What have these two Beetles in common as
regards shape? I mean by shape not the structural details which the
classifier examines through his magnifying-glass, not the delicate features
which a Latreille would quote when drawing up a technical description, but
the general picture, the general outline that impresses itself upon the
vision even of an untrained eye and makes the man who knows nothing of
science and above all the child, a most perspicacious observer, connect
certain animals together.

In this respect, what have the Brachyderes and the Balaninus in common in
the eyes of the townsman, the peasant, the child or the Cerceris?
Absolutely nothing. The first has an almost cylindrical figure; the second,
squat, short and thickset, is conical in front and elliptical, or rather
shaped like the ace of hearts, behind. The first is black, strewn with
cloudy, mouse-grey spots; the second is yellow ochre. The head of the first
ends in a sort of snout; the head of the second tapers into a curved beak,
slender as a horse-hair and as long as the rest of the body. The
Brachyderes has a massive proboscis, cut off short; the Balaninus seems to
be smoking an insanely long cigarette-holder.

Who would think of connecting two creatures so unlike, of calling them by
the same name? Outside the professional classifiers, no one would dare to.
The Cerceris, more perspicacious, knows each of them for a Weevil, a quarry
with a concentrated nervous system, lending itself to the surgical feat of
her single stroke of the lancet. After obtaining an abundant booty at the
cost of the blunt-mouthed insect, with which she sometimes stuffs her
cellars to the exclusion of any other fare, according to the hazards of the
chase, she now suddenly sees before her the creature with the extravagant
proboscis. Accustomed to the first, will she fail to know the second? By no
means: at the first glance she recognizes it as her own; and the cell
already furnished with a few Brachyderes receives its complement of
Balanini. If these two species are to seek, if the burrows are far from the
holm-oaks, the Cerceris will attack Weevils displaying the greatest variety
of genus, species, form and coloration, levying tribute indifferently on
Sitones, Cneorhini, Geonemi, Otiorhynchi, Strophosomi and many others.

In vain do I rack my brains merely to guess at the signs upon which the
huntress relies as a guide, without going outside one and the same group,
in the midst of such a variety of game; above all by what characteristics
she recognizes as a Weevil the strange Acorn Balaninus, the only one among
her victims that wears a long pipe-stem. I leave to evolutionism, atavism
and other transcendental "isms" the honour and also the risk of explaining
what I humbly recognize as being too far beyond my grasp. Because the son
of the bird-catcher who imitates the call of his victims has been fed on
roast Robins, Linnets and Chaffinches, shall we hastily conclude that this
education through the stomach will enable him later, without other
initiation than that of the spit, to know his way about the ornithological
groups and to avoid confusing them when his turn comes to set his limed
twigs? Will the digesting of a ragout of little birds, however often
repeated by him or his ascendants, suffice to make him a finished bird-
catcher? The Cerceris has eaten Weevil; her ancestors have all eaten
Weevil, religiously. If you see in this the reason that makes the Wasp a
Weevil-expert endowed with a perspicacity unrivalled save by that of a
professional entomologist, why should you refuse to admit that the same
consequences would follow in the bird-catcher's family?

I hasten to abandon these insoluble problems in order to attack the
question of provisions from another point of view. Every Hunting Wasp is
confined to a certain genus of game, which is usually strictly limited. She
pursues her appointed quarry and regards anything outside it with suspicion
and distaste. The tricks of the experimenter, who drags her prey from under
her and flings her another in exchange, the emotions of the possessor
deprived of her property and immediately recovering it, but under another
form, are powerless to put her on the wrong scent. Obstinately she refuses
whatever is alien to her portion; instantly she accepts whatever forms part
of it. Whence arises this insuperable repugnance for provisions to which
the family is unaccustomed? Here we may appeal to experiment. Let us do so:
its dictum is the only one that can be trusted.

The first idea that presents itself and the only one, I think, that can
present itself is that the larva, the carnivorous nurseling, has its
preferences, or we had better say its exclusive tastes. This kind of game
suits it; that does not; and the mother provides it with food in conformity
with its appetites, which are unchangeable in each species. Here the family
dish is the Gad-fly; elsewhere it is the Weevil; elsewhere again it is the
Cricket, the Locust and the Praying Mantis. Good in themselves, in a
general way, these several victuals may be noxious to a consumer who is not
used to them. The larva which dotes on Locust may find caterpillar a
detestable fare; and that which revels in caterpillar may hold Locust in
horror. It would be hard for us to discover in what manner Cricket-flesh
and Ephippiger-flesh differ as juicy, nourishing foodstuffs; but it does
not follow that the two Sphex-wasps addicted to this diet have not very
decided opinions on the matter, or that each of them is not filled with the
highest esteem for its traditional dish and a profound dislike for the
other. There is no discussing tastes.

Moreover, the question of health may well be involved. There is nothing to
tell us that the Spider, that treat for the Pompilus, is not poison, or at
least unwholesome food, to the Bembex, the lover of Gad-flies; that the
Ammophila's succulent caterpillar is not repugnant to the stomach of the
Sphex fed upon the dry Acridian. The mother's esteem for one kind of game
and her distrust of another would in that case be due to the likes and
dislikes of her larvae; the victualler would regulate the bill of fare by
the gastronomic demands of the victualled.

This exclusiveness of the carnivorous larva seems all the more probable
inasmuch as the larva reared on vegetable food refuses in any way to lend
itself to a change of diet. However pressed by hunger, the caterpillar of
the Spurge Hawk-moth, which browses on the tithymals, will allow itself to
starve in front of a cabbage leaf which makes a peerless meal for the
Pieris. Its stomach, burned by pungent spices, will find the Crucifera
insipid and uneatable, though its piquancy is enhanced by essence of
sulphur. The Pieris, on its part, takes good care not to touch the
tithymals: they would endanger its life. The caterpillar of the Death's-
head Hawk-moth requires the solanaceous narcotics, principally the potato,
and will have nothing else. All that is not seasoned with solanin it
abhors. And it is not only larvae whose food is strongly spiced with
alkaloids and other poisonous substances that refuse any innovation in
their food; the others, even those whose diet is least juicy, are
invincibly uncompromising. Each has its plant or its group of plants,
beyond which nothing is acceptable.

I remember a late frost which had nipped the buds of the mulberry-trees
during the night, just when the first leaves were out. Next day there was
great excitement among my neighbours: the Silk-worms had hatched and the
food had suddenly failed. The farmers had to wait for the sun to repair the
disaster; but how were they to keep the famishing new-born grubs alive for
a few days? They knew me for an expert in plants; by collecting them as I
walked through the fields I had earned the name of a medical herbalist.
With poppy-flowers I prepared an elixir which cleared the sight; with
borage I obtained a syrup which was a sovran remedy for whooping-cough; I
distilled camomile; I extracted the essential oil from the wintergreen. In
short, botany had won for me the reputation of a quack doctor. After all,
that was something.

The housewives came in search of me from every point of the compass and
with tears in their eyes explained the situation. What could they give
their Silk-worms while waiting for the mulberry to sprout afresh? It was a
serious matter, well worthy of commiseration. One was counting on her batch
to buy a length of cloth for her daughter, who was on the point of getting
married; another told me of her plans for a Pig to be fattened against the
coming winter; all deplored the handful of crown-pieces which, hoarded in
the hiding-place in the cupboard, would have afforded help in difficult
times. And, full of their troubles, they unfolded, before my eyes, a scrap
of flannel on which the vermin were swarming:

"Regardas, moussu! Venoun d'espeli; et ren per lour douna! Ah, pecaire!"
"Look, sir! The frost has come and we've nothing to give them! Oh, what a
misfortune!"

Poor people! What a harsh trade is yours: respectable above all others, but
of all the most uncertain! You work yourselves to death; and, when you have
almost reached your goal, a few hours of a cold night, which comes upon you
suddenly, destroys your harvest. To help these afflicted ones seemed to me
a very difficult thing. I tried, however, taking botany as my guide; it
suggested to me, as substitutes for the mulberry, the members of closely-
related families: the elm, the nettle-tree, the nettle, the pellitory.
Their nascent leaves, chopped small, were offered to the Silk-worms. Other
and far less logical attempts were made, in accordance with the inspiration
of the individuals. Nothing came of them. To the last specimen, the new-
born Silk-worms died of hunger. My renown as a quack must have suffered
somewhat from this check. Was it really my fault? No, it was the fault of
the Silk-worm, which remained faithful to its mulberry leaf.

It was therefore in nearly the certainty of non-fulfilment that I made my
first attempts at rearing carnivorous larvae with a quarry which did not
conform with the customary regimen. For conscience' sake, more or less
perfunctorily, I endeavoured to achieve something that seemed to me bound
to end in pitiful failure. Only the Bembex-wasps, which are plentiful in
the sand of the neighbouring hills, might still afford me, without too
prolonged a search, a few subjects on which to experiment. The Tarsal
Bembex furnished me with what I wanted: larvae young enough to have still
before them a long period of feeding and yet sufficiently developed to
endure the trials of a removal.

These larva are exhumed with all the consideration which their delicate
skin demands; a number of head of game are likewise unearthed intact,
having been recently brought by the mother. They consist of various
Diptera, including some Anthrax-flies. (Cf. "The Life of the Fly": chapters
2 and 4.--Translator's Note.) An old sardine-box, containing a layer of
sifted sand and divided into compartments by paper partitions, receives my
charges, who are isolated one from another. These Fly-eaters I propose to
turn into Grasshopper-eaters; for their Bembex-diet I intend to substitute
the diet of a Sphex or a Tachytes. To save myself tedious errands devoted
to provisioning the refectory, I accept what good fortune offers me at the
very threshold of my door. A green Locustid, with a short sabre bent into a
reaping-hook, Phaneroptera falcata, is ravaging the corollae of my
petunias. Now is the time to indemnify myself for the damage which she has
caused me. I pick her young, half to three-quarters of an inch in length;
and I deprive her of movement, without more ado, by crushing her head. In
this condition she is served up to the Bembex-larvae in place of their
Flies.

If the reader has shared my convictions of failure, convictions based on
very logical motives, he will now share my profound surprise. The
impossible becomes possible, the senseless becomes reasonable and the
expected becomes the opposite of the real. The dish served on the Bembeces'
table for the first time since Bembeces came into the world is accepted
without any repugnance and consumed with every mark of satisfaction. I will
here set down the detailed diary of one of my guests; that of the others
would only be a repetition, save for a few variations.

2 AUGUST, 1883.--The larva of the Bembex, as I extract it from its burrow,
is about half-developed. Around it I find only some scanty relics of its
meals, consisting chiefly of Anthrax-wings, half-diaphanous and half-
clouded. The mother would appear to have completed the victualling by fresh
contributions, added day by day. I give the nurseling, which is an Anthrax-
eater, a young Phaneroptera. The Locustid is attacked without hesitation.
This profound change in the character of its victuals does not seem in the
least to disturb the larva, which bites straight into the rich morsel with
its mandibles and does not let go until it has exhausted it. Towards
evening the drained carcase is replaced by another, quite fresh, of the
same species but bulkier, measuring over three-quarters of an inch.

3 AUGUST.--Next day I find the Phaneroptera devoured. Nothing remains but
the dry integuments, which are not dismembered. The entire contents have
disappeared; the game has been emptied through a large opening made in the
belly. A regular Grasshopper-eater could not have operated more skilfully.
I replace the worthless carcase by two small Locustidae. At first the larva
does not touch them, being amply sated with the copious meal of the day
before. In the afternoon, however, one of the items is resolutely attacked.

4 AUGUST.--I renew the victuals, although those of the day before are not
finished. For the rest, I do the same daily, so that my charge may
constantly have fresh food at hand. High game might upset its stomach. My
Locustidae are not victims at the same time living and inert, operated upon
according to the delicate method of the insects that paralyse their prey;
they are corpses, procured by a brutal crushing of the head. With the
temperature now prevailing, flesh soon becomes tainted; and this compels me
frequently to renew the provisions in my sardine-box refectory. Two
specimens are served up. One is attacked soon afterwards; and the larva
clings to it assiduously.

5 AUGUST.--The ravenous appetite of the start is becoming assuaged. My
supplies may well be too generous; and it might be prudent to try a little
dieting after this Gargantuan good cheer. The mother certainly is more
parsimonious. If all the family were to eat at the same rate as my guest,
she would never be able to keep pace with their demands. Therefore, for
reasons of health, this is a day of fasting and vigil.

6 AUGUST.--Supplies are renewed with two Phaneropterae. One is consumed
entirely; the other is bitten into.

7 August.--To-day's ration is tasted and then abandoned. The larva seems
uneasy. With its pointed mouth it explores the walls of its chamber. This
sign denotes the approach of the time for making the cocoon.

8 AUGUST.--During the night the larva has spun its silken eel-trap. It is
now encrusting it with grains of sand. Then follow, in due time, the normal
phases of the metamorphosis. Fed on Locustidae, a diet unknown to its race,
the larva passes through its several stages without any more difficulty
than its brothers and sisters fed on Flies.

I obtained the same success in offering young Mantes for food. One of the
larvae thus served would even incline me to believe that it preferred the
new dish to the traditional diet of its race. Two Eristales, or Drone-
flies, and a Praying Mantis an inch long composed its daily allowance. The
Drone-flies are disdained from the first mouthful; and the Mantis, already
tasted and apparently found excellent, causes the Fly to be completely
forgotten. Is this an epicure's preference, due to the greater juiciness of
the flesh? I am not in a position to say. At all events, the Bembex is not
so infatuated with Fly as to refuse to abandon it for other game.

The failure which I foresaw has proved a magnificent success. It is fairly
convincing, is it not? Without the evidence of experiment, what can we rely
upon? Beneath the ruins of so many theories which appeared to be most
solidly erected I should hesitate to admit that two and two make four if
the facts were not before me. My argument had the most tempting probability
on its side, but it had not the truth. As it is always possible to find
reasons after the event in support of an opinion which one would not at
first admit, I should now argue as follows:

The plant is the great factory in which are elaborated, with mineral
materials, the organic principles which are the materials of life. Certain
products are common to the whole vegetable series, but others, far less
numerous, are prepared in special laboratories. Each genus, each species
has its trade-mark. Here essential oils are manufactured; here alkaloids;
here starches, fatty substances, resins, sugars, acids. Hence result
special energies, which do not suit every herbivorous animal. It assuredly
requires a stomach made expressly for the purpose to digest aconite,
colchicum, hemlock or henbane; those who have not such a stomach could
never endure a diet of that sort. Besides, the Mithridates fed on poison
resist only a single toxin. (Mithridates VI. King of Pontus (d. B.C. 63) is
said to have secured immunity from poison by taking increased doses of it.-
-Translator's Note.) The caterpillar of the Death's-head Hawk-moth, which
delights in the solanin of the potato, would be killed by the acrid
principle of the tithymals that form the food of the Spurge-caterpillar.
The herbivorous larvae are therefore perforce exclusive in their tastes,
because different genera of vegetables possess very different properties.

With this variety in the products of the plant, the animal, a consumer far
more than a producer, contrasts the uniformity in its own products. The
albumen in the egg of the Ostrich or the Chaffinch, the casein in the milk
of the Cow or the Ass, the muscular flesh of the Wolf or the Sheep, the
Screech-owl or the Field-mouse, the Frog or the Earth-worm: these remain
albumen, casein or fibrin, edible if not eaten. Here are no excruciating
condiments, no special acridities, no alkaloids fatal to any stomach other
than that of the appointed consumer; so that animal food is not confined to
one and the same eater. What does not man eat, from that delicacy of the
arctic regions, soup made of Seal's blood and a scrap of Whale-blubber
wrapped in a willow-leaf for a vegetable, to the Chinaman's fried Silk-worm
or the Arab's dried Locust? What would he not eat, if he had not to
overcome the repugnance dictated by habit rather than by actual necessity?
The prey being uniform in its nutritive principles, the carnivorous larva
ought to accommodate itself to any sort of game, above all if the new dish
be not too great a departure from consecrated usage. Thus should I argue,
with no less probability on my side, had I to begin all over again. But, as
all our arguments have not the value of a single fact, I should be forced
in the end to resort to experiment.

I did so the next year, on a larger scale and with a greater variety of
subjects. I shrink from a continuous narrative of my experiments and of my
personal education in this new art, where the failure of one day taught me
the way to succeed on the morrow. It would be long and tedious. Enough if I
briefly state my results and the conditions which must be fulfilled in
order to run the delicate refectory as it should be run.

And, first, we must not dream of detaching the egg from its natural prey to
lay it on another. The egg adheres pretty firmly, by its cephalic pole, to
the quarry. To remove it from its place would inevitably jeopardize its
future. I therefore let the larva hatch and acquire sufficient strength to
bear the removal without peril. For that matter, my excavations most often
provide me with my subjects in the form of larvae. I adopt for rearing-
purposes the larvae that are a quarter to a half developed. The others are
too young and risky to handle, or too old and limited to a short period of
artificial feeding.

Secondly, I avoid bulky heads of game, a single one of which would suffice
for the whole growing-stage. I have already said and I here repeat how nice
a matter it is to consume a victim which has to keep fresh for a couple of
weeks and not to finish dying until it is almost entirely devoured. Death
here leaves no corpse; when life is extinct, the body has disappeared,
leaving only a shred of skin. Larvae with only one large prey have a
special art of eating, a dangerous art, in which a clumsy bite would prove
fatal. If bitten before the proper time at such a point, the victim becomes
putrid, which promptly causes death by poisoning in the consumer. When
diverted from its plan of attack, deprived of its clue, the larva is not
always able to rediscover the lawful morsels in good time and is killed by
the decomposition of its badly dissected prey. What will happen if the
experimenter gives it a game to which it is not accustomed? Not knowing how
to eat it according to rule, the larva will kill it; and by next day the
victuals will have become so much toxic putrescence. I have already told
how I found it impossible to rear the Two-banded Scolia on Oryctes-larvae,
fastened down to deprive them of movement, or even on Ephippigers,
paralysed by the Languedocian Sphex. In both cases the new diet was
accepted without hesitation, a proof that it suited the nurseling; but in a
day or two putrescence supervened and the Scolia perished on the fetid
morsel. The method of preserving the Ephippiger, so well known to the
Sphex, was unknown to my boarder; in this was enough to convert a delicious
food into poison.

Even so did my other attempts miscarry wretchedly, attempts at feeding with
the single dish consisting of one big head of game to replace the normal
ration. Only one success is recorded in my notebooks, but that was so
difficult that I would not undertake to obtain it a second time. I
succeeded in feeding the larva of the Hairy Ammophila with an adult black
Cricket, who was accepted as readily as the natural game, the caterpillar.

To avoid putrefaction of victuals which last overlong and are not consumed
according to the method indispensable to their preservation, I employ small
game, each piece of which can be finished by the larva at a single sitting,
or at most in a single day. It matters little then that the victim is
slashed and dismembered at random; decomposition has no time to seize upon
its still quivering tissues. This is the procedure of those larvae which
gulp down their food, snapping at random without distinguishing one part
from another, such as the Bembex-larvae, which finish the Fly into which
they have bitten before beginning another in the heap, or the Cerceris-
larvae, which drain their Weevils methodically one after another. With the
first strokes of the mandibles the victim broached may be mortally wounded.
This is no disadvantage: a brief spell suffices to make use of the corpse,
which is saved from putrefaction by being promptly consumed. Close beside
it, the other victims, quite alive though motionless, await their
respective turns and supply reserves of victuals which are always fresh.

I am too unskilful a butcher to imitate the Wasp and myself to resort to
paralysis; moreover, the caustic liquid injected into the nerve-centres,
ammonia in particular, would leave traces of smell or flavour which might
put off my boarders. I am therefore compelled to deprive my insects of the
power of movement by killing them outright. This makes it impracticable to
provide a sufficiency of provisions beforehand in a single supply: while
one item of the ration was being consumed the rest would spoil. One
expedient alone remains to me, one which entails constant attendance: it is
to renew the provisions each day. When all these conditions are fulfilled,
the success of artificial feeding is still not without its difficulties;
nevertheless, with a little care and above all plenty of patience, it is
almost certain.

It was thus that I reared the Tarsal Bembex, which eats Anthrax-flies and
other Diptera, on young Locustidae or Mantidae; the Silky Ammophila, whose
diet consists chiefly of Measuring-worms, on small Spiders; the pot-making
Pelopaeus, a Spider-eater, on tender Acridians; the Sand Cerceris, a
passionate lover of Weevils, on Halicti; the Bee-eating Philanthus, which
feeds exclusively on Hive-bees, on Eristales and other Flies. Without
succeeding in my final aim, for reasons which I have just explained, I have
seen the Two-banded Scolia feasting greedily on the grub of the Oryctes,
which was substituted for that of the Cetonia, and putting up with an
Ephippiger taken from the burrow of the Sphex; I have been present at the
repast of three Hairy Ammophilae accepting with an excellent appetite the
Cricket that replaced their caterpillar. One of them, as I have related,
contrived to keep its ration fresh, which enabled it to reach its full
development and to spin its cocoon.

These examples, the only ones to which my experiments have extended
hitherto, seem to me sufficiently convincing to allow me to conclude that
the carnivorous larva does not have exclusive tastes. The ration supplied
to it by the mother, so monotonous, so limited in quality, might be
replaced by others equally to its taste. Variety does not displease the
larva; it does it as much good as uniformity; indeed, it would be of
greater benefit to the race, as we shall see presently.

CHAPTER 8. A DIG AT THE EVOLUTIONISTS.

To rear a caterpillar-eater on a skewerful of Spiders is a very innocent
thing, unlikely to compromise the security of the State; it is also a very
childish thing, as I hasten to confess, and worthy of the schoolboy who, in
the mysteries of his desk, seeks as best he may some diversion from the
fascinations of his exercise in composition. And I should not have
undertaken these investigations, still less should I have spoken them, not
without some satisfaction, if I had not discerned, in the results obtained
in my refectory, a certain philosophic import, involving, so it seemed to
me, the evolutionary theory.

It is assuredly a majestic enterprise, commensurate with man's immense
ambitions, to seek to pour the universe into the mould of a formula and
submit every reality to the standard of reason. The geometrician proceeds
in this manner: he defines the cone, an ideal conception; then he
intersects it by a plane. The conic section is submitted to algebra, an
obstetrical appliance which brings forth the equation; and behold,
entreated now in one direction, now in another, the womb of the formula
gives birth to the ellipse, the hyperbola, the parabola, their foci, their
radius vectors, their tangents, their normals, their conjugate axes, their
asymptotes and the rest. It is magnificent, so much so that you are
overcome by enthusiasm, even when you are twenty years old, an age hardly
adapted to the austerities of mathematics. It is superb. You feel as if you
were witnessing the creation of a world.

As a matter of fact, you are merely observing the same idea from different
points of view, which are illumined by the successive phases of the
transformed formula. All that algebra unfolds for our benefit was contained
in the definition of the cone, but it was contained as a germ, under latent
forms which the magic of the calculus converts into explicit forms. The
gross value which our mind confided to the equation it returns to us,
without loss or gain, in coins stamped with every sort of effigy. And here
precisely is that which constitutes the inflexible rigour of the calculus,
the luminous certainty before which every cultivated mind is forced to bow.
Algebra is the oracle of the absolute truth, because it reveals nothing but
what the mind had hidden in it under an amalgam of symbols. We put 2 and 2
into the machine; the rollers work and show us 4. That is all.

But to this calculus, all-powerful so long as it does not leave the domain
of the ideal, let us submit a very modest reality: the fall of a grain of
sand, the pendular movement of a hanging body. The machine no longer works,
or does so only by suppressing almost everything that is real. It must have
an ideal material point, an ideal rigid thread, an ideal point of
suspension; and then the pendular movement is translated by a formula. But
the problem defies all the artifices of analysis if the oscillating body is
a real body, endowed with volume and friction; if the suspensory thread is
a real thread, endowed with weight and flexibility; if the point of support
is a real point, endowed with resistance and capable of deflection. So with
other problems, however simple. The exact reality escapes the formula.

Yes, it would be a fine thing to put the world into an equation, to assume
as the first principle a cell filled with albumen and by transformation
after transformation to discover life under its thousand aspects as the
geometrician discovers the ellipse and the other curves by examining his
conic section. Yes, it would be magnificent and enough to add a cubit to
our stature. Alas, how greatly must we abate our pretensions! The reality
is beyond our reach when it is only a matter of following a grain of dust
in its fall; and we would undertake to ascend the river of life and trace
it to its source! The problem is a more arduous one than that which algebra
declines to solve. There are formidable unknown quantities here, more
difficult to decipher than the resistances, the deflections and the
frictions of the pendulum. Let us eliminate them, that we may more easily
propound the theory.

Very well; but then my confidence in this natural history which repudiates
nature and gives ideal conceptions precedence over real facts is shaken.
So, without seeking the opportunity, which is not my business, I take it
when it presents itself; I examine the theory of evolution from every side;
and, as that which I have been assured is the majestic dome of a monument
capable of defying the ages appears to me to be no more than a bladder, I
irreverently dig my pin into it.

Here is the latest dig. Adaptability to a varied diet is an element of
well-being in the animal, a factor of prime importance for the extension
and predominance of its race in the bitter struggle for life. The most
unfortunate species would be that which depended for its existence on a
diet so exclusive that no other could replace it. What would become of the
Swallow if he required, in order to live, one particular Gnat, a single
Gnat, always the same? When once this Gnat had disappeared--and the life of
the Mosquito is not a long one--the bird would die of starvation.
Fortunately for himself and for the happiness of our homes, the Swallow
gulps them all down indiscriminately, together with a host of other insects
that perform aerial ballets. What would become of the Lark were his gizzard
able to digest only one seed, invariably the same? When the season for this
seed was over--and the season is always a short one--the haunter of the
furrows would perish.

Is not man's complaisant stomach, adapted to the largest variety of
nourishment, one of his great zoological privileges? He is thus rendered
independent of climates, seasons and latitudes. And the Dog: how is it that
of all the domestic animals he alone is able to accompany us everywhere,
even on the most arduous expeditions? The Dog again is omnivorous and
therefore a cosmopolitan.

The discovery of a new dish, said Brillat-Savarin, is of greater importance
to humanity than the discovery of a new planet. The aphorism is nearer to
the truth than it appears to be in its humorous form. Certainly the man who
was the first to think of crushing wheat, kneading flour and cooking the
paste between two hot stones was more deserving than the discoverer of the
two-hundredth asteroid. The invention of the potato is certainly as
valuable as that of Neptune, glorious as the latter was. All that increases
our alimentary resources is a discovery of the first merit. And what is
true of man cannot be other than true of animals. The world belongs to the
stomach which is independent of specialities. This truth is of the kind
that has only to be stated to be proved.

Let us now return to our insects. If I am to believe the evolutionists, the
various game-hunting Wasps are descended from a small number of types,
which are themselves derived, by an incalculable number of concatenations,
from a few amoebae, a few monera and lastly from the first clot of
protoplasm which was casually condensed. Let us not go back as far as that;
let us not plunge into the fogs where illusion and error too easily find a
lurking-place. Let us consider a subject with exact limits to it; this is
the only way to understand one another.

The Sphegidae are descended from a single type, which itself was already a
highly-developed descendant and, like its successors, fed its family on
prey. The close similarity in form, in colouring and, above all, in habits
seem to refer the Tachytes to the same origin. This is ample; let us be
satisfied with it. And now please tell me, what did this prototype of the
Sphegidae hunt? Was its diet varied or uniform? If we cannot decide, let us
examine the two cases.

The diet was varied. I heartily congratulate the first born of the Sphex-
wasps. She enjoyed the most favourable conditions for leaving a prosperous
offspring. Accommodating herself to any kind of prey not disproportionate
to her strength, she avoided the dearth of a given species of game at this
or that time and in this or that place; she always found the wherewithal to
endow her family magnificently, they being, for that matter, fairly
indifferent to the nature of the victuals, provided that these consisted of
fresh insect-flesh, as the tastes of their cousins many times removed prove
to this day. This matriarch of the Sphex clan bore within herself the best
chances of assuring victory to her offspring in that pitiless fight for
existence which eliminates the weakly and incapable and allows none but the
strong and industrious to survive; she possessed an aptitude of great value
which atavism could not fail to hand down and which her descendants, who
are greatly interested in preserving this magnificent inheritance, must
have permanently adopted and even accentuated from one generation to the
next, from one branch, one offshoot, to another.

Instead of this unscrupulously omnivorous race, levying booty upon every
kind of game, to its very great advantage, what do we see to-day? Each
Sphex is stupidly limited to an unvarying diet; she hunts only one kind of
prey, though her larva accepts them all. One will have nothing but the
Ephippiger and must have a female at that; another will have nothing but

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More Hunting WaspsbyJ. Henri Fabre

Part 2 out of 4

More Hunting Wasps
by
J. Henri Fabre