site logo


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. Lik
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


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


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


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


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.