VIEW THE MOBILE VERSION of www.bugsinsects.net Informational Site Network Informational
Privacy
   Home - Articles - Books

THE COTTON-BEES




The evidence of the Leaf-cutters proves that a certain latitude is
left to the insect in its choice of materials for the nest; and this
is confirmed by the testimony of the Anthidia, the cotton-
manufacturers. My district possesses five: A. Florentinum, LATR., A.
diadema, LATR., A. manicatum, LATR., A. cingulatum, LATR., A.
scapulare, LATR. None of them creates the refuge in which the cotton
goods are manufactured. Like the Osmiae and the Leaf-cutters, they
are homeless vagrants, adopting, each to her own taste, such shelter
as the work of others affords. The Scapular Anthidium is loyal to the
dry bramble, deprived of its pith and turned into a hollow tube by
the industry of various mining Bees, among which figure, in the front
rank, the Ceratinae, dwarf rivals of the Xylocopa, or Carpenter-bee,
that mighty driller of rotten wood. The spacious galleries of the
Masked Anthophora suit the Florentine Anthidium, the foremost member
of the genus so far as size is concerned. The Diadem Anthidium
considers that she has done very well if she inherits the vestibule
of the Hairy-footed Anthophora, or even the ordinary burrow of the
Earth-worm. Failing anything better, she may establish herself in the
dilapidated dome of the Mason-bee of the Pebbles. The Manicate
Anthidium shares her tastes. I have surprised the Girdled Anthidium
cohabiting with a Bembex-wasp. The two occupants of the cave dug in
the sand, the owner and the stranger, were living in peace, both
intent upon their business. Her usual habitation is some hole or
other in the crevices of a ruined wall. To these refuges, the work of
others, we can add the stumps of reeds, which are as popular with the
various cotton-gatherers as with the Osmiae; and, after we have
mentioned a few most unexpected retreats, such as the sheath provided
by a hollow brick or the labyrinth furnished by the lock of a gate,
we shall have almost exhausted the list of domiciles.

Like the Osmiae and the Leaf-cutters, the Anthidium shows an urgent
need of a ready-made home. She never houses herself at her own
expense. Can we discover the reason? Let us first consult a few hard
workers who are artificers of their own dwellings. The Anthophora
digs corridors and cells in the road-side banks hardened by the sun;
she does not erect, she excavates; she does not build, she clears.
Toiling away with her mandibles, atom by atom, she manages to
contrive the passages and chambers necessary for her eggs; and a huge
business it is. She has, in addition, to polish and glaze the rough
sides of her tunnels. What would happen if, after obtaining a home by
dint of long-continued toil, she had next to line it with wadding, to
gather the fibrous down from cottony plants and to felt it into bags
suitable for the honey-paste? The hard-working Bee would not be equal
to producing all these refinements. Her mining calls for too great an
expenditure of time and strength to leave her the leisure for
luxurious furnishing. Chambers and corridors, therefore, will remain
bare.

The Carpenter-bee gives us the same answer. When with her joiner's
wimble she has patiently bored the beam to a depth of nine inches,
would she be able to cut out and place in position the thousand and
one pieces which the Silky Leaf-cutter employs for her nest? Time
would fail her, even as it would fail a Megachile who, lacking the
Capricorn's chamber, had herself to dig a home in the trunk of the
oak. Therefore the Carpenter-bee, after the tedious work of boring,
gets the installation done in the most summary fashion, simply
running up a sawdust partition.

The two things, the laborious business of obtaining a lodging and the
artistic work of furnishing, seem unable to go together. With the
insect as with man, he who builds the house does not furnish it, he
who furnishes it does not build it. To each his share, because of
lack of time. Division of labour, the mother of the arts, makes the
workman excel in his department; one man for the whole work would
mean stagnation, the worker never getting beyond his first crude
attempts. Animal industry is a little like our own: it does not
attain its perfection save with the aid of obscure toilers, who,
without knowing it, prepare the final masterpiece. I see no other
reason for this need of a gratuitous lodging for the Megachile's
leafy basket or the Anthidia's cotton purses. In the case of other
artists who handle delicate things that require protection, I do not
hesitate to assume the existence of a ready-made home. Thus Reaumur
tells us of the Upholsterer-bee, Anthocopa papaveris, who fashions
her cells with poppy-petals. I do not know the flower-cutter, I have
never seen her; but her art tells me plainly enough that she must
establish herself in some gallery wrought by others, as, for
instance, in an Earth-worm's burrow.

We have but to see the nest of a Cotton-bee to convince ourselves
that its builder cannot at the same time be an indefatigable navvy.
When and newly-felted and not yet made sticky with honey, the wadded
purse is by far the most elegant known specimen of entomological
nest-building, especially where the cotton is of a brilliant white,
as is frequently the case in the manufacturers of the Girdled
Anthidium. No bird's-nest, however deserving of our admiration, can
vie in fineness of flock, in gracefulness of form, in delicacy of
felting with this wonderful bag, which our fingers, even with the aid
of tools, could hardly imitate, for all their dexterity. I abandon
the attempt to understand how, with its little bales of cotton
brought up one by one, the insect, no otherwise gifted than the
kneaders of mud and the makers of leafy baskets, manages to felt what
it has collected into a homogeneous whole and then to work the
product into a thimble-shaped wallet. Its tools as a master-fuller
are its legs and its mandibles, which are just like those possessed
by the mortar-kneaders and Leaf-cutters; and yet, despite this
similarity of outfit, what a vast difference in the results obtained!

To see the Cotton-bees' talents in action seems an undertaking
fraught with innumerable difficulties: things happen at a depth
inaccessible to the eye; and to persuade the insect to work in the
open does not lie in our power. One resource remained and I did not
fail to turn to it, though hitherto I have been wholly unsuccessful.
Three species, Anthidium diadema, A. manicatum and A. florentinum--
the first-named in particular--show themselves quite ready to take up
their abode in my reed-apparatus. All that I had to do was to replace
the reeds by glass tubes, which would allow me to watch the work
without disturbing the insect. This stratagem had answered perfectly
with the Three-horned Osmia and Latreille's Osmia, whose little
housekeeping-secrets I had learnt thanks to the transparent dwelling-
house. Why should it not answer for its Cotton-bees and, in the same
way, with the Leaf-cutters? I almost counted on success. Events
betrayed my confidence. For four years I supplied my hives with glass
tubes and not once did the Cotton-weavers or the Leaf-cutters
condescend to take up their quarters in the crystal palaces. They
always preferred the hovel provided by the reed. Shall I persuade
them one day? I do not abandon all hope.

Meanwhile, let me describe the little that I saw. More or less
stocked with cells, the reed is at last closed, right at the orifice,
with a thick plug of cotton, usually coarser than the wadding of the
honey-satchels. It is the equivalent of the Three-horned Osmia's
barricade of mud, of the leaf-putty of Latreille's Osmia, of the
Megachiles' barrier of leaves cut into disks. All these free tenants
are careful to shut tight the door of the dwelling, of which they
have often utilized only a portion. To watch the building of this
barricade, which is almost external work, demands but a little
patience in waiting for the favourable moment.

The Anthidium arrives at last, carrying the bale of cotton for the
plugging. With her fore-legs she tears it apart and spreads it out;
with her mandibles, which go in closed and come out open, she loosens
the hard lumps of flock; with her forehead she presses each new layer
upon the one below. And that is all. The insect flies off, returns
the richer by another bale and repeats the performance until the
cotton barrier reaches the level of the opening. We have here,
remember, a rough task, in no way to be compared with the delicate
manufacturer of the bags; nevertheless, it may perhaps tell us
something of the general procedure of the finer work. The legs do the
carding, the mandibles the dividing, the forehead the pressing; and
the play of these implements produces the wonderful cushioned wallet.
That is the mechanism in the lump; but what of the artistry?

Let us leave the unknown for facts within the scope of observation. I
will question the Diadem Anthidium in particular, a frequent inmate
of my reeds. I open a reed-stump about two decimetres long by twelve
millimetres in diameter. (About seven and three-quarter inches by
half an inch.--Translator's Note.) The end is occupied by a column of
cotton-wool comprising ten cells, without any demarcation between
them on the outside, so that their whole forms a continuous cylinder.
Moreover, thanks to a close felting, the different compartments are
soldered together, so much so that, when pulled by the end, the
cotton edifice does not break into sections, but comes out all in one
piece. One would take it for a single cylinder, whereas in reality
the work is composed of a series of chambers, each of which has been
constructed separately, independently of the one before, except
perhaps at the base.

For this reason, short of ripping up the soft dwelling, still full of
honey, it is impossible to ascertain the number of storeys; we must
wait until the cocoons are woven. Then our fingers can tell the cells
by counting the knots that resist pressure under the cover of
wadding. This general structure is easily explained. A cotton bag is
made, with the sheath of the reed as a mould. If this guiding sheath
were lacking, the thimble shape would be obtained all the same, with
no less elegance, as is proved by the Girdled Anthidium, who makes
her nest in some hiding-place or other in the walls or the ground.
When the purse is finished, the provisions come and the egg, followed
by the closing of the cell. We do not here find the geometrical lid
of the Leaf-cutters, the pile of disks tight-set in the mouth of the
jar. The bag is closed with a cotton sheet whose edges are soldered
by a felting-process to the edges of the opening. The soldering is so
well done that the honey-pouch and its cover form an indivisible
whole. Immediately above it, the second cell is constructed, having
its own base. At the beginning of this work, the insect takes care to
join the two storeys by felting the ceiling of the first to the floor
of the second. Thus continued to the end, the work, with its inner
solderings, becomes an unbroken cylinder, in which the beauties of
the separate wallets disappear from view. In very much the same
fashion, but with less adhesion among the different cells, do the
Leaf-cutters act when stacking their jars in a column without any
external division into storeys.

Let us return to the reed-stump which gives us these details. Beyond
the cotton-wool cylinder wherein ten cocoons are lodged in a row
comes an empty space of half a decimetre or more. (About two inches.-
-Translator's Note.) The Osmiae and the Leaf-cutters are also
accustomed to leave these long, deserted vestibules. The nest ends,
at the orifice of the reed, with a strong plug of flock coarser and
less white than that of the cells. This use of closing-materials
which are less delicate in texture but of greater resisting-power,
while not an invariable characteristic, occurs frequently enough to
make us suspect that the insect knows how to distinguish what is best
suited now to the snug sleeping-berth of the larvae, anon to the
defensive barricade of the home. Sometimes the choice is an
exceedingly judicious one, as is shown by the nest of the Diadem
Anthidium. Time after time, whereas the cells were composed of the
finest grade of white cotton, gathered from Centaurea solsticialis,
or St. Barnaby's thistle, the barrier at the entrance, differing from
the rest of the work in its yellow colouring, was a heap of close-set
bristles supplied by the scallop-leaved mullein. The two functions of
the wadding are here plainly marked. The delicate skin of the larvae
needs a well-padded cradle; and the mother collects the softest
materials that the cottony plants provide. Rivalling the bird, which
furnishes the inside of the nest with wool and strengthens the
outside with sticks, she reserves for the grubs' mattress the finest
down, so hard to find and collected with such patience. But, when it
becomes a matter of shutting the door against the foe, then the
entrance bristles with forbidding caltrops, with stiff, prickly
hairs.

This ingenious system of defence is not the only one known to the
Anthidia. More distrustful still, the Manicate Anthidium leaves no
space in the front part of the reed. Immediately after the column of
cells, she heaps up, in the uninhabited vestibule, a conglomeration
of rubbish, whatever chance may offer in the neighbourhood of the
nest: little pieces of gravel, bits of earth, grains of sawdust,
particles of mortar, cypress-catkins, broken leaves, dry Snail-
droppings and any other material that comes her way. The pile, a real
barricade this time, blocks the reed completely to the end, except
about two centimetres (About three-quarters of an inch.--Translator's
Note.) left for the final cotton plug. Certainly no foe will break in
through the double rampart; but he will make an insidious attack from
the rear. The Leucopsis will come and, with her long probe, thanks to
some imperceptible fissure in the tube, will insert her dread eggs
and destroy every single inhabitant of the fortress. Thus are the
Manicate Anthidium's anxious precautions outwitted.

If we had not already seen the same thing with the Leaf-cutters, this
would be the place to enlarge upon the useless tasks undertaken by
the insect when, with its ovaries apparently depleted, it goes on
spending its strength with no maternal object in view and for the
sole pleasure of work. I have come across several reeds stopped up
with flock though containing nothing at all, or else furnished with
one, two or three cells devoid of provisions or eggs. The ever-
imperious instinct for gathering cotton and felting it into purses
and heaping it into barricades persists, fruitlessly, until life
fails. The Lizard's tail wriggles, curls and uncurls after it is
detached from the animal's body. In these reflex movements, I seem to
see not an explanation, certainly, but a rough image of the
industrious persistency of the insect, still toiling away at its
business, even when there is nothing useful left to do. This worker
knows no rest but death.

I have said enough about the dwelling of the Diadem Anthidium; let us
look at the inhabitant and her provisions. The honey is pale-yellow,
homogeneous and of a semifluid consistency, which prevents it from
trickling through the porous cotton bag. The egg floats on the
surface of the heap, with the end containing the head dipped into the
paste. To follow the larva through its progressive stages is not
without interest, especially on account of the cocoon, which is one
of the most singular that I know. With this object in view, I prepare
a few cells that lend themselves to observation. I take a pair of
scissors, slice a piece off the side of the cotton-wool purse, so as
to lay bare both the victuals and the consumer, and place the ripped
cell in a short glass tube. During the first few days, nothing
striking happens. The little grub, with its head still plunged in the
honey, slakes its thirst with long draughts and waxes fat. A moment
comes...But let us go back a little farther, before broaching this
question of sanitation.

Every grub, of whatever kind, fed on provisions collected by the
mother and placed in a narrow cell is subject to conditions of health
unknown to the roving grub that goes where it likes and feeds itself
on what it can pick up. The first, the recluse, is no more able than
the second, the gadabout, to solve the problem of a food which can be
entirely assimilated, without leaving an unclean residue. The second
gives no thought to these sordid matters: any place suits it for
getting rid of that difficulty. But what will the other do with its
waste matter, cooped up as it is in a tiny cell stuffed full of
provisions? A most unpleasant mixture seems inevitable. Picture the
honey-eating grub floating on liquid provisions and fouling them at
intervals with its excretions! The least movement of the hinder-part
would cause the whole to amalgamate; and what a broth that would make
for the delicate nursling! No, it cannot be; those dainty epicures
must have some method of escaping these horrors.

They all have, in fact, and most original methods at that. Some take
the bull by the horns, so to speak, and, in order not to soil things,
refrain from uncleanliness until the end of the meal: they keep the
dropping-trap closed as long as the victuals are unfinished. This is
a radical scheme, but not in every one's power, it appears. It is the
course adopted, for instance, by the Sphex-wasps and the Anthophora-
bees, who, when the whole of the food is consumed, expel at one shot
the residues amassed in the intestines since the commencement of the
repast.

Others, the Osmiae in particular, accept a compromise and begin to
relieve the digestive tract when a suitable space has been made in
the cell through the gradual disappearance of the victuals. Others
again--more hurried these--find means of obeying the common law
pretty early by engaging in stercoral manufactures. By a stroke of
genius, they make the unpleasant obstruction into building-bricks. We
already know the art of the Lily-beetle (Crioceris merdigera. Fabre's
essay on this insect has not yet been translated into English; but
readers interested in the matter will find a full description in "An
Introduction to Entomology," by William Kirby, Rector of Barham, and
William Spence: letter 21.--Translator's Note.), who, with her soft
excrement, makes herself a coat wherein to keep cool in spite of the
sun. It is a very crude and revolting art, disgusting to the eye. The
Diadem Anthidium belongs to another school. With her droppings she
fashions masterpieces of marquetry and mosaic, which wholly conceal
their base origin from the onlooker. Let us watch her labours through
the windows of my tubes.

When the portion of food is nearly half consumed, there begins and
goes on to the end a frequent defecation of yellowish droppings, each
hardly the size of a pin's head. As these are ejected, the grub
pushes them back to the circumference of the cell with a movement of
its hinder-part and keeps them there by means of a few threads of
silk. The work of the spinnerets, therefore, which is deferred in the
others until the provisions are finished, starts earlier here and
alternates with the feeding. In this way, the excretions are kept at
a distance, away from the honey and without any danger of getting
mixed with it. They end by becoming so numerous as to form an almost
continuous screen around the larva. This excremental awning, made
half of silk and half of droppings, is the rough draft of the cocoon,
or rather a sort of scaffolding on which the stones are deposited
until they are definitely placed in position. Pending the piecing
together of the mosaic, the scaffolding keeps the victuals free from
all contamination.

To get rid of what cannot be flung outside, by hanging it on the
ceiling, is not bad to begin with; but to use it for making a work of
art is better still. The honey has disappeared. Now commences the
final weaving of the cocoon. The grub surrounds itself with a wall of
silk, first pure white, then tinted reddish-brown by means of an
adhesive varnish. Through its loose-meshed stuff, it seizes one by

one the droppings hanging from the scaffold and inlays them firmly in
the tissue. The same mode of work is employed by the Bembex-, Stizus-
and Tachytes-wasps and other inlayers, who strengthen the inadequate
woof of their cocoons with grains of sand; only, in their cotton-wool
purses, the Anthidium's grubs substitute for the mineral particles
the only solid materials at their disposal. For them, excrement takes
the place of pebbles.

And the work goes none the worse for it. On the contrary: when the
cocoon is finished, any one who had not witnessed the process of
manufacture would be greatly puzzled to state the nature of the
workmanship. The colouring and the elegant regularity of the outer
wrapper of the cocoon suggest some kind of basket-work made with tiny
bits of bamboo, or a marquetry of exotic granules. I too let myself
be caught by it in my early days and wondered in vain what the hermit
of the cotton wallet had used to inlay her nymphal dwelling so
prettily withal. To-day, when the secret is known to me, I admire the
ingenuity of the insect capable of obtaining the useful and the
beautiful out of the basest materials.

The cocoon has another surprise in store for us. The end containing
the head finishes with a short conical nipple, an apex, pierced by a
narrow shaft that establishes a communication between the inside and
the out. This architectural feature is common to all the Anthidia, to
the resin-workers who will occupy our attention presently, as well as
to the cotton-workers. It is found nowhere outside the Anthidium
group.

What is the use of this point which the larva leaves bare instead of
inlaying it like the rest of the shell? What is the use of that hole,
left quite open or, at most, closed at the bottom with a feeble
grating of silk? The insect appears to attach great importance to it,
from what I see. In point of fact, I watch the careful work of the
apex. The grub, whose movements the hole enables me to follow,
patiently perfects the lower end of the conical channel, polishes it
and gives it an exactly circular shape; from time to time, it inserts
into the passage its two closed mandibles, whose points project a
little way outside; then, opening them to a definite radius, like a
pair of compasses, it widens the aperture and makes it regular.

I imagine, without venturing, however, to make a categorical
statement, that the perforated apex is a chimney to admit the air
required for breathing. Every pupa breathes in its shell, however
compact this may be, even as the unhatched bird breathes inside the
egg. The thousands of pores with which the shell is pierced allow the
inside moisture to evaporate and the outer air to penetrate as and
when needed. The stony caskets of the Bembex- and Stizus-wasps are
endowed, notwithstanding their hardness, with similar means of
exchange between the vitiated and the pure atmosphere. Can the shells
of the Anthidia be air-proof, owing to some modification that escapes
me? In any case, this impermeability cannot be attributed to the
excremental mosaic, which the cocoons of the resin-working Anthidia
do not possess, though endowed with an apex of the very best.

Shall we find an answer to the question in the varnish with which the
silken fabric is impregnated? I hesitate to say yes and I hesitate to
say no, for a host of cocoons are coated with a similar lacquer
though deprived of communication with the outside air. All said,
without being able at present to account for its necessity, I admit
that the apex of the Anthidia is a breathing-aperture. I bequeath to
the future the task of telling us for what reasons the collectors of
both cotton and resin leave a large pore in their shells, whereas all
the other weavers close theirs completely.

After these biological curiosities, it remains for me to discuss the
principal subject of this chapter: the botanical origin of the
materials of the nest. By watching the insect when busy at its
harvesting, or else by examining its manufactured flock under the
microscope, I was able to learn, not without a great expenditure of
time and patience, that the different Anthidia of my neighbourhood
have recourse without distinction to any cottony plant. Most of the
wadding is supplied by the Compositae, particularly the following:
Centaurea solsticialis, or St. Barnaby's thistle; C. paniculata, or
panicled centaury; Echinops ritro, or small globe-thistle; Onopordon
illyricum, or Illyrian cotton-thistle; Helichrysum staechas, or wild
everlasting; Filago germanica, or common cotton-rose. Next come the
Labiatae: Marrubium vulgare, or common white horehound; Ballota
fetida, or stinking horehound; Calamintha nepeta, or lesser calamint;
Salvia aethiopis, or woolly sage. Lastly, the Solanaceae: Verbascum
thapsus, or shepherd's club; V. sinuatum, or scollop-leaved mullein.

The Cotton-bees' flora, we see, incomplete as it is in my notes,
embraces plants of very different aspect. There is no resemblance in
appearance between the proud candelabrum of the cotton-thistle, with
its red tufts, and the humble stalk of the globe-thistle, with its
sky-blue capitula; between the plentiful leaves of the mullein and
the scanty foliage of the St. Barnaby's thistle; between the rich
silvery fleece of the woolly sage and the short hairs of the
everlasting. With the Anthidium, these clumsy botanical
characteristics do not count; one thing alone guides her: the
presence of cotton. Provided that the plant be more or less well-
covered with soft wadding, the rest is immaterial to her.

Another condition, however, has to be fulfilled, apart from the
fineness of the cotton-wool. The plant, to be worth shearing, must be
dead and dry. I have never seen the harvesting done on fresh plants.
In this way, the Bee avoids mildew, which would make its appearance
in a mass of hairs still filled with sap.

Faithful to the plant recognized as yielding good results, the
Anthidium arrives and resumes her gleaning on the edges of the parts
denuded by earlier harvests. Her mandibles scrape away and pass the
tiny fluffs, one by one, to the hind-legs, which hold the pellet
pressed against the chest, mix with it the rapidly-increasing store
of down and make the whole into a little ball. When this is the size
of a pea, it goes back into the mandibles; and the insect flies off,
with its bale of cotton in its mouth. If we have the patience to
wait, we shall see it return to the same point, at intervals of a few
minutes, so long as the bag is not made. The foraging for provisions
will suspend the collecting of cotton; then, next day or the day
after, the scraping will be resumed on the same stalk, on the same
leaf, if the fleece be not exhausted. The owner of a rich crop
appears to keep to it until the closing-plug calls for coarser
materials; and even then this plug is often manufactured with the
same fine flock as the cells.

After ascertaining the diversity of cotton-fields among our native
plants, I naturally had to enquire whether the Cotton-bee would also
put up with exotic plants, unknown to her race; whether the insect
would show any hesitation in the presence of woolly plants offered
for the first time to the rakes of her mandibles. The common clary
and the Babylonian centaury, with which I have stocked the harmas,
shall be the harvest-fields; the reaper shall be the Diadem
Anthidium, the inmate of my reeds.

The common clary, or toute-bonne, forms part, I know, of our French
flora to-day; but it is an acclimatized foreigner. They say that a
gallant crusader, returning from Palestine with his share of glory
and bruises, brought back the toute-bonne from the Levant to help him
cure his rheumatism and dress his wounds. From the lordly manor, the
plant propagated itself in all directions, while remaining faithful
to the walls under whose shelter the noble dames of yore used to grow
it for their unguents. To this day, feudal ruins are its favourite
resorts. Crusaders and manors disappeared; the plant remained. In
this case, the origin of the clary, whether historical or legendary,
is of secondary importance. Even if it were of spontaneous growth in
certain parts of France, the toute-bonne is undoubtedly a stranger in
the Vaucluse district. Only once in the course of my long botanizing-
expeditions across the department have I come upon this plant. It was
at Caromb, in some ruins, nearly thirty years ago. I took a cutting
of it; and since then the crusaders' sage has accompanied me on all
my peregrinations. My present hermitage possesses several tufts of
it: but, outside the enclosure, except at the foot of the walls, it
would be impossible to find one. We have, therefore, a plant that is
new to the country for many miles around, a cotton-field which the
Serignan Cotton-bees had never utilized before I came and sowed it.

Nor had they ever made use of the Babylonian centaury, which I was
the first to introduce in order to cover my ungrateful stony soil
with some little vegetation. They had never seen anything like the
colossal centaury imported from the region of the Euphrates. Nothing
in the local flora, not even the cotton-thistle, had prepared them
for this stalk as thick as a child's wrist, crowned at a height of
nine feet with a multitude of yellow balls, nor for those great
leaves spreading over the ground in an enormous rosette. What will
they do in the presence of such a find? They will take possession of
it with no more hesitation than if it were the humble St. Barnaby's
thistle, the usual purveyor.

In fact, I place a few stalks of clary and Babylonian centaury, duly
dried, near the reed-hives. The Diadem Anthidium is not long in
discovering the rich harvest. Straight away the wool is recognized as
being of excellent quality, so much so that, during the three or four
weeks of nest-building, I can daily witness the gleaning, now on the
clary, now on the centaury. Nevertheless the Babylonian plant appears
to be preferred, no doubt because of its whiter, finer and more
plentiful down. I keep a watchful eye on the scraping of the
mandibles and the work of the legs as they prepare the pellet; and I
see nothing that differs from the operations of the insect when
gleaning on the globe-thistle and the St. Barnaby's thistle. The
plant from the Euphrates and the plant from Palestine are treated
like those of the district.

Thus we find what the Leaf-cutters taught us proved, in another way,
by the cotton-gatherers. In the local flora, the insect has no
precise domain; it reaps its harvest readily now from one species,
now from another, provided that it find the materials for its
manufactures. The exotic plant is accepted quite as easily as that of
indigenous growth. Lastly, the change from one plant to another, from
the common to the rare, from the habitual to the exceptional, from
the known to the unknown, is made suddenly, without gradual
initiations. There is no novitiate, no training by habit in the
choice of the materials for the nest. The insect's industry, variable
in its details by sudden, individual and non-transmissible
innovations, gives the lie to the two great factors of evolution:
time and heredity.





Next: THE RESIN-BEES

Previous: THE LEAF-CUTTERS



Add to del.icio.us Add to Reddit Add to Digg Add to Del.icio.us Add to Google Add to Twitter Add to Stumble Upon
Add to Informational Site Network
Report
Privacy
SHAREADD TO EBOOK