CHAPTER 14. THE HALICTI: PARTHENOGENESIS.

The Halictus opens up another question, connected with one of life's

obscurest problems. Let us go back five-and-twenty years. I am living at

Orange. My house stands alone among the fields. On the other side of

the wall enclosing our yard, which faces due south, is a narrow path

overgrown with couch-grass. The sun beats full upon it; and the glare

reflected from the whitewash of the wall turns it into a little tropical

corner, shut off from the rude gusts of the north-west wind.

Here the Cats come to take their afternoon nap, with their eyes

half-closed; here the children come, with Bull, the House-dog; here

also come the haymakers, at the hottest time of the day, to sit and take

their meal and whet their scythes in the shade of the plane-tree; here

the women pass up and down with their rakes, after the hay-harvest, to

glean what they can on the niggardly carpet of the shorn meadow. It is

therefore a very much frequented footpath, were it only because of the

coming and going of our household: a thoroughfare ill-suited, one would

think, to the peaceful operations of a Bee; and nevertheless it is such

a very warm and sheltered spot and the soil is so favourable that every

year I see the Cylindrical Halictus (H. cylindricus, FAB.) hand down

the site from one generation to the next. It is true that the very

matutinal, even partly nocturnal character of the work makes the insect

suffer less inconvenience from the traffic.

The burrows cover an extent of some ten square yards, and their mounds,

which often come near enough to touch, average a distance of four inches

at the most from one another. Their number is therefore something like

a thousand. The ground just here is very rough, consisting of stones

and dust mixed with a little mould and held together by the closely

interwoven roots of the couch-grass. But, owing to its nature, it is

thoroughly well drained, a condition always in request among Bees and

Wasps that have underground cells.

Let us forget for a moment what the Zebra Halictus and the Early

Halictus have taught us. At the risk of repeating myself a little,

I will relate what I observed during my first investigations. The

Cylindrical Halictus works in May. Except among the social species, such

as Common Wasps, Bumble-bees, Ants and Hive-bees, it is the rule for

each insect that victuals its nests either with honey or game to work by

itself at constructing the home of its grubs. Among insects of the same

species there is often neighbourship; but their labours are individual

and not the result of co-operation. For instance, the Cricket-hunters,

the Yellow-winged Sphex, settle in gangs at the foot of a sandstone

cliff, but each digs her own burrow and would not suffer a neighbour to

come and help in piercing the home.

In the case of the Anthophorae, an innumerable swarm takes possession

of a sun-scorched crag, each Bee digging her own gallery and jealously

excluding any of her fellows who might venture to come to the entrance

of her hole. The Three-pronged Osmia, when boring the bramble-stalk

tunnel in which her cells are to be stacked, gives a warm reception to

any Osmia that dares set foot upon her property.

Let one of the Odyneri who make their homes in a road-side bank mistake

the door and enter her neighbour's house: she would have a bad time of

it! Let a Megachile, returning with her leafy disk in her legs, go

into the wrong basement: she would be very soon dislodged! So with the

others: each has her own home, which none of the others has the right

to enter. This is the rule, even among Bees and Wasps established in a

populous colony on a common site. Close neighbourhood implies no sort of

intimate relationship.

Great therefore is my surprise as I watch the Cylindrical Halictus'

operations. She forms no society, in the entomological sense of the

word: there is no common family; and the general interest does not

engross the attention of the individual. Each mother occupies herself

only with her own eggs, builds cells and gathers honey only for her own

larvae, without concerning herself in any way with the upbringing of the

others' grubs. All that they have in common is the entrance-door and

the goods-passage, which ramifies in the ground and leads to different

groups of cells, each the property of one mother. Even so, in the blocks

of flats in our large towns, one door, one hall and one staircase lead

to different floors or different portions of a floor where each family

retains its isolation and its independence.

This common right of way is extremely easy to perceive at the time for

victualling the nests. Let us direct our attention for a while to the

same entrance-aperture, opening at the top of a little mound of earth

freshly thrown up, like that accumulated by the Ants during their works.

Sooner or later we shall see the Halicti arrive with their load of

pollen, gathered on the Cichoriaceae of the neighbourhood.

Usually, they come up one by one; but it is not rare to see three, four

or even more appearing at the same time at the mouth of one burrow.

They perch on the top of the mound and, without hurrying in front of one

another, with no sign of jealousy, they dive down the passage, each

in her turn. We need but watch their peaceful waiting, their tranquil

dives, to recognize that this indeed is a common passage to which each

has as much right as another.

When the soil is exploited for the first time and the shaft sunk slowly

from the outside to the inside, do several Cylindrical Halicti, one

relieving the other, take part in the work by which they will afterwards

profit equally? I do not believe it for a moment. As the Zebra Halictus

and the Early Halictus told me later, each miner goes to work alone and

makes herself a gallery which will be her exclusive property. The common

use of the passage comes presently, when the site, tested by experience,

is handed down from one generation to another.

A first group of cells is established, we will suppose, at the bottom of

a pit dug in virgin soil. The whole thing, cells and pit, is the work of

one insect. When the moment comes to leave the underground dwelling, the

Bees emerging from this nest will find before them an open road, or one

at most obstructed by crumbly matter, which offers less resistance than

the neighbouring soil, as yet untouched. The exit-way will therefore be

the primitive way, contrived by the mother during the construction of

the nest. All enter upon it without any hesitation, for the cells open

straight on it. All, coming and going from the cells to the bottom

of the shaft and from the shaft to the cells, will take part in the

clearing, under the stimulus of the approaching deliverance.

It is quite unnecessary here to presume among these underground

prisoners a concerted effort to liberate themselves more easily by

working in common: each is thinking only of herself and invariably

returns, after resting, to toil at the inevitable path, the path of

least resistance, in short the passage once dug by the mother and now

more or less blocked up.

Among the Cylindrical Halicti, any one who wishes emerges from her

cell at her own hour, without waiting for the emergence of the others,

because the cells, grouped in small stacks, have each their special

outlet opening into the common gallery. The result of this arrangement

is that all the inhabitants of one burrow are able to assist, each doing

her share, in the clearing of the exit-shaft. When she feels fatigued,

the worker retires to her undamaged cell and another succeeds her,

impatient to get out rather than to help the first. At last the way is

clear and the Halicti emerge. They disperse over the flowers around as

long as the sun is hot; when the air cools, they go back to the burrows

to spend the night there.

A few days pass and already the cares of egg-laying are at hand. The

galleries have never been abandoned. The Bees have come to take refuge

there on rainy or very windy days; most, if not all, have returned every

evening at sunset, each doubtless making for her own cell, which is

still intact and which is carefully impressed upon her memory. In a

word, the Cylindrical Halictus does not lead a wandering life; she has a

fixed residence.

A necessary consequence results from these settled habits: for the

purpose of her laying, the Bee will adopt the identical burrow in which

she was born. The entrance-gallery is ready therefore. Should it need to

be carried deeper, to be pushed in new directions, the builder has but

to extend it at will. The old cells even can serve again, if slightly

restored.

Thus resuming possession of the native burrow in view of her offspring,

the Bee, notwithstanding her instincts as a solitary worker, achieves

an attempt at social life, because there is one entrance-door and

one passage for the use of all the mothers returning to the original

domicile. There is thus a semblance of collaboration without any real

co-operation for the common weal. Everything is reduced to a family

inheritance shared equally among the heirs.

The number of these coheirs must soon be limited, for a too tumultuous

traffic in the corridor would delay the work. Then fresh passages are

opened inwards, often communicating with depths already excavated,

so that the ground at last is perforated in every direction with an

inextricable maze of winding tunnels.

The digging of the cells and the piercing of new galleries take place

especially at night. A cone of fresh earth on top of the burrow bears

evidence every morning to the overnight activity. It also shows by its

volume that several navvies have taken part in the work, for it would be

impossible for a single Halictus to extract from the ground, convey to

the surface and heap up so large a stack of rubbish in so short a time.

At sunrise, when the fields around are still wet with dew, the

Cylindrical Halictus leaves her underground passages and starts on her

foraging. This is done without animation, perhaps because of the morning

coolness. There is no joyous excitement, no humming above the burrows.

The Bees come back again, flying low, silently and heavily, their

hind-legs yellow with pollen; they alight on the earth-cone and at once

dive down the vertical chimney. Others come up the pipe and go off to

their harvesting.

This journeying to and fro for provisions continues until eight or nine

in the morning. Then the heat begins to grow intense and is reflected

by the wall; then also the path is once more frequented. People pass at

every moment, coming out of the house or elsewhence. The soil is so much

trodden under foot that the little mounds of refuse surrounding each

burrow soon disappear and the site loses every sign of underground

habitation.

All day long, the Halicti remain indoors. Withdrawing to the bottom of

the galleries, they occupy themselves probably in making and polishing

the cells. Next morning, new cones of rubbish appear, the result of the

night's work, and the pollen-harvest is resumed for a few hours; then

everything ceases again. And so the work goes on, suspended by day,

renewed at night and in the morning hours, until completely finished.

The passages of the Cylindrical Halictus descend to a depth of some

eight inches and branch into secondary corridors, each giving access

to a set of cells. These number six or eight to each set and are ranged

side by side, parallel with their main axis, which is almost horizontal.

They are oval at the base and contracted at the neck. Their length is

nearly twenty millimetres (.78 inch.--Translator's Note.) and their

greatest width eight. (.312 inch.--Translator's Note.) They do not

consist simply of a cavity in the ground; on the contrary, they have

their own walls, so that the group can be taken out in one piece, with

a little precaution, and removed neatly from the earth in which it is

contained.

The walls are formed of fairly delicate materials, which must have

been chosen in the coarse surrounding mass and kneaded with saliva.

The inside is carefully polished and upholstered with a thin waterproof

film. We will cut short these details concerning the cells, which the

Zebra Halictus has already shown us in greater perfection, leave the

home to itself and come to the most striking feature in the life-history

of the Halicti.

The Cylindrical Halictus is at work in the first days of May. It is

a rule among the Hymenoptera for the males never to take part in

the fatiguing work of nest-building. To construct cells and to amass

victuals are occupations entirely foreign to their nature. This rule

seems to have no exceptions; and the Halicti conform to it like the

rest. It is therefore only to be expected that we should see no males

shooting the underground rubbish outside the galleries. That is not

their business.

But what does astonish us, when our attention is directed to it, is the

total absence of any males in the vicinity of the burrows. Although it

is the rule that the males should be idle, it is also the rule for these

idlers to keep near the galleries in course of construction, coming and

going from door to door and hovering above the work-yards to seize the

moment at which the unfecundated females will at last yield to their

importunities.

Now here, despite the enormous population, despite my careful and

incessant watch, it is impossible for me to distinguish a single male.

And yet the distinction between the sexes is of the simplest. It is

not necessary to take hold of the male. He can be recognized even at a

distance by his slenderer frame, by his long, narrow abdomen, by his red

sash. They might easily suggest two different species. The female is

a pale russet-brown; the male is black, with a few red segments to his

abdomen. Well, during the May building-operations, there is not a Bee in

sight clad in black, with a slender, red-belted abdomen; in short, not a

male.

Though the males do not come to visit the environs of the burrows, they

might be elsewhere, particularly on the flowers where the females go

plundering. I did not fail to explore the fields, insect-net in hand.

My search was invariably fruitless. On the other hand, those males,

now nowhere to be found, are plentiful later, in September, along the

borders of the paths, on the close-set flowers of the eringo.

This singular colony, reduced exclusively to mothers, made me suspect

the existence of several generations a year, whereof one at least must

possess the other sex. I continued therefore, when the building-who

was over, to keep a daily watch on the establishment of the Cylindrical

Halictus, in order to seize the favourable moment that would verify my

suspicions. For six weeks, solitude reigned above the burrows: not a

single Halictus appeared; and the path, trodden by the wayfarers, lost

its little heaps of rubbish, the only signs of the excavations. There

was nothing outside to show that the warmth down below was hatching

populous swarms.

July comes and already a few little mounds of fresh earth betoken work

going on underground in preparation for an exodus in the near future.

As the males, among the Hymenoptera, are generally further advanced than

the females and quit their natal cells earlier, it was important that I

should witness the first exits made, so as to dispel the least shadow

of a doubt. A violent exhumation would have a great advantage over the

natural exit: it would place the population of the burrows immediately

under my eyes, before the departure of either sex. In this way, nothing

could escape from me and I was dispensed from a watch which, for all its

attentiveness, was not to be relied upon absolutely. I therefore resolve

upon a reconnaissance with the spade.

I dig down to the full depth of the galleries and remove large lumps of

earth which I take in my hands and break very carefully so as to examine

all the parts that may contain cells. Halicti in the perfect state

predominate, most of them still lodged in their unbroken chambers.

Though they are not quite so numerous, there are also plenty of pupae.

I collect them of every shade of colour, from dead-white, the sign of

a recent transformation, to smoky-brown, the mark of an approaching

metamorphosis. Larvae, in small quantities, complete the harvest. They

are in the state of torpor that precedes the appearance of the pupa.

I prepare boxes with a bed of fresh, sifted earth to receive the larvae

and the pupae, which I lodge each in a sort of half-cell formed by the

imprint of my finger. I will await the transformation to decide to which

sex they belong. As for the perfect insects, they are inspected, counted

and at once released.

In the very unlikely supposition that the distribution of the sexes

might vary in different parts of the colony, I make a second excavation,

at a few yards' distance from the other. It supplies me with another

collection both of perfect insects and of pupae and larvae.

When the metamorphosis of the laggards is completed, which does not take

many days, I proceed to take a general census. It gives me two hundred

and fifty Halicti. Well, in this number of Bees, collected in the burrow

before any have emerged, I perceive none, absolutely none but females;

or, to be mathematically accurate, I find just one male, one alone;

and he is so small and feeble that he dies without quite succeeding in

divesting himself of his nymphal bands. This solitary male is certainly

accidental. A female population of two hundred and forty-nine Halicti

implies other males than this abortion, or rather implies none at all. I

therefore eliminate him as an accident of no value and conclude that, in

the Cylindrical Halictus, the July generation consists of females only.

The building-operations start again in the second week of July. The

galleries are restored and lengthened; new cells are fashioned and the

old ones repaired. Follow the provisioning, the laying of the eggs, the

closing of the cells; and, before July is over, there is solitude again.

Let me also say that, during the building-period, not a male appears in

sight, a fact which adds further proof to that already supplied by my

excavations.

With the high temperature of this time of the year, the development of

the larvae makes rapid progress: a month is sufficient for the various

stages of the metamorphosis. On the 24th of August there are once more

signs of life above the burrows of the Cylindrical Halictus, but under

very different conditions. For the first time, both sexes are present.

Males, so easily recognized by their black livery and their slim abdomen

adorned with a red ring, hover backwards and forwards, almost level with

the ground. They fuss about from burrow to burrow. A few rare females

come out for a moment and then go in again.

I proceed to make an excavation with my spade; I gather indiscriminately

whatever I come across. Larvae are very scarce; pupae abound, as do

perfect insects. The list of my captures amounts to eighty males and

fifty-eight females. The males, therefore, hitherto impossible to

discover, either on the flowers around or in the neighbourhood of the

burrows, could be picked up to-day by the hundred, if I wished. They

outnumber the females by about four to three; they are also further

developed, in accordance with the general rule, for most of the backward

pupae give me only females.

Once the two sexes had appeared, I expected a third generation that

would spend the winter in the larval state and recommence in May the

annual cycle which I have just described. My anticipation proved to be

at fault. Throughout September, when the sun beats upon the burrows,

I see the males flitting in great numbers from one shaft to the other.

Sometimes a female appears, returning from the fields, but with no

pollen on her legs. She seeks her gallery, finds it, dives down and

disappears.

The males, as though indifferent to her arrival, offer her no welcome,

do not harass her with their amorous pursuits; they continue to visit

the doors of the burrows with a winding and oscillating flight. For two

months, I follow their evolutions. If they set foot on earth, it is to

descend forthwith into some gallery that suits them.

It is not uncommon to see several of them on the threshold of the same

burrow. Then each awaits his turn to enter; they are as peaceable in

their relations as the females who are joint owners of a burrow. At

other times, one wants to go in as a second is coming out. This sudden

encounter produces no strife. The one leaving the hole withdraws a

little to one side to make enough room for two; the other slips past as

best he can. These peaceful meetings are all the more striking when we

consider the usual rivalry between males of the same species.

No rubbish-mound stands at the mouth of the shafts, showing that the

building has not been resumed; at the most, a few crumbs of earth are

heaped outside. And by whom, pray? By the males and by them alone. The

lazy sex has bethought itself of working. It turns navvy and shoots out

grains of earth that would interfere with its continual entrances and

exits. For the first time I witness a custom which no Hymenopteron had

yet shown me: I see the males haunting the interior of the burrows with

an assiduity equalling that of the mothers employed in nest-building.

The cause of these unwonted operations soon stands revealed. The females

seen flitting above the burrows are very rare; the majority of the

feminine population remain sequestered under ground, do not perhaps come

out once during the whole of the latter part of summer. Those who do

venture out go in again soon, empty-handed of course and always without

any amorous teasing from the males, a number of whom are hovering above

the burrows.

On the other hand, watch as carefully as I may, I do not discover

a single act of pairing out of doors. The weddings are clandestine,

therefore, and take place under ground. This explains the males' fussy

visits to the doors of the galleries during the hottest hours of the

day, their continual descents into the depths and their continual

reappearances. They are looking for the females cloistered in the

retirement of the cells.

A little spade-work soon turns suspicion into certainty. I unearth a

sufficient number of couples to prove to me that the sexes come together

underground. When the marriage is consummated, the red-belted one quits

the spot and goes to die outside the burrow, after dragging from flower

to flower the bit of life that remains to him. The other shuts herself

up in her cell, there to await the return of the month of May.

September is spent by the Halictus solely in nuptial celebrations.

Whenever the sky is fine, I witness the evolutions of the males above

the burrows, with their continual entrances and exits; should the sun

be veiled, they take refuge down the passages. The more impatient,

half-hidden in the pit, show their little black heads outside, as though

peeping for the least break in the clouds that will allow them to pay a

brief visit to the flowers round about. They also spend the night in the

burrows. In the morning, I attend their levee; I see them put their head

to the window, take a look at the weather and then go in again until the

sun beats on the encampment.

The same mode of life is continued throughout October, but the males

become less numerous from day to day as the stormy season approaches

and fewer females remain to be wooed. By the time that the first cold

weather comes, in November, complete solitude reigns over the burrows.

I once more have recourse to the spade. I find none but females in their

cells. There is not one male left. All have vanished, all are dead, the

victims of their life of pleasure and of the wind and rain. Thus ends

the cycle of the year for the Cylindrical Halictus.

In February, after a hard winter, when the snow had lain on the ground

for a fortnight, I wanted once more to look into the matter of my

Halicti. I was in bed with pneumonia and at the point of death, to all

appearances. I had little or no pain, thank God, but extreme difficulty

in living. With the little lucidity left to me, being able to do no

other sort of observing, I observed myself dying; I watched with a

certain interest the gradual falling to pieces of my poor machinery.

Were it not for the terror of leaving my family, who were still young, I

would gladly have departed. The after-life must have so many higher and

fairer truths to teach us.

My hour had not yet come. When the little lamps of thought began to

emerge, all flickering, from the dusk of unconsciousness, I wished to

take leave of the Hymenopteron, my fondest joy, and first of all of my

neighbour, the Halictus. My son Emile took the spade and went and dug

the frozen ground. Not a male was found, of course; but there were

plenty of females, numbed with the cold in their cells.

A few were brought for me to see. Their little chambers showed no

efflorescence of rime, with which all the surrounding earth was coated.

The waterproof varnish had been wonderfully efficacious. As for the

anchorites, roused from their torpor by the warmth of the room, they

began to wander about my bed, where I followed them vaguely with my

fading eyes.

May came, as eagerly awaited by the sick man as by the Halicti. I left

Orange for Serignan, my last stage, I expect. While I was moving, the

Bees resumed their building. I gave them a regretful glance, for I had

still much to learn in their company. I have never since met with such a

mighty colony.

These old observations on the habits of the Cylindrical Halictus may now

be followed by a general summary which will incorporate the recent data

supplied by the Zebra Halictus and the Early Halictus.

The females of the Cylindrical Halictus whom I unearth from November

onwards are evidently fecundated, as is proved by the assiduity of the

males during the preceding two months and most positively confirmed by

the couples discovered in the course of my excavations. These females

spend the winter in their cells, as do many of the early-hatching

melliferous insects, such as Anthophorae and Mason-bees, who build their

nests in the spring, the larvae reaching the perfect state in the summer

and yet remaining shut up in their cells until the following May. But

there is this great difference in the case of the Cylindrical Halictus,

that in the autumn the females leave their cells for a time to receive

the males under ground. The couples pair and the males perish. Left

alone, the females return to their cells, where they spend the inclement

season.

The Zebra Halicti, studied first at Orange and then, under better

conditions, at Serignan, in my own enclosure, have not these

subterranean customs: they celebrate their weddings amid the joys of

the light, the sun and the flowers. I see the first males appear in the

middle of September, on the centauries. Generally there are several of

them courting the same bride. Now one, then another, they swoop upon her

suddenly, clasp her, leave her, seize hold of her again. Fierce brawls

decide who shall possess her. One is accepted and the others decamp.

With a swift and angular flight, they go from flower to flower, without

alighting. They hover on the wing, looking about them, more intent on

pairing than on eating.

The Early Halictus did not supply me with any definite information,

partly through my own fault, partly through the difficulty of excavation

in a stony soil, which calls for the pick-axe rather than the spade. I

suspect her of having the nuptial customs of the Cylindrical Halictus.

There is another difference, which causes certain variations of detail

in these customs. In the autumn, the females of the Cylindrical Halictus

leave their burrows seldom or not at all. Those who do go out invariably

come back after a brief halt upon the flowers. All pass the winter in

the natal cells. On the other hand, those of the Zebra Halictus move

their quarters, meet the males outside and do not return to the burrows,

which my autumn excavations always find deserted. They hibernate in the

first hiding-places that offer.

In the spring, the females, fecundated since the autumn, come out:

the Cylindrical Halicti from their cells, the Zebra Halicti from their

various shelters, the Early Halicti apparently from their chambers, like

the first. They work at their nests in the absence of any male, as do

also the Social Wasps, whose whole brood has perished excepting a few

mothers also fecundated in the autumn. In both cases, the assistance of

the males is equally real, only it has preceded the laying by about six

months.

So far, there is nothing new in the life of the Halicti; but here is

where the unexpected appears: in July, another generation is produced;

and this time without males. The absence of masculine assistance is no

longer a mere semblance here, due to an earlier fecundation: it is a

reality established beyond a doubt by the continuity of my observations

and by my excavations during the summer season, before the emergence of

the new Bees. At this period, a little before July, if my spade unearth

the cells of any one of my three Halicti, the result is always females,

nothing but females, with exceedingly rare exceptions.

True, it may be said that the second progeny is due to the mothers who

knew the males in autumn and who would be able to nidify twice a year.

The suggestion is not admissible. The Zebra Halictus confirms what

I say. She shows us the old mothers no longer leaving the home but

mounting guard at the entrance to the burrows. No harvesting- or

pottery-work is possible with these absorbing doorkeeping-functions.

Therefore there is no new family, even admitting that the mothers'

ovaries are not depleted.

I do not know if a similar argument is valid in the case of the

Cylindrical Halictus. Has she any general survivors? As my attention

had not yet been directed on this point in the old days, when I had

the insect at my door, I have no records to go upon. For all that, I

am inclined to think that the portress of the Zebra Halictus is unknown

here. The reason of this absence would be the number of workers at the

start.

In May, the Zebra Halictus, living by herself in her winter retreat,

founds her house alone. When her daughters succeed her, in July, she is

the only grandmother in the establishment and the post of portress falls

to her. With the Cylindrical Halictus, the conditions are different.

Here the May workers are many in the same burrow, where they dwell in

common during the winter. Supposing that they survive when the business

of the household is finished, to whom will the office of overseer fall?

Their number is so great and they are all so full of zeal that disorder

would be inevitable. But we can leave this small matter unsettled

pending further information.

The fact remains that females, females exclusively, have come out of the

eggs laid in May. They have descendants, of that there is no room for

doubt; they procreate though there are no males in their time. From

this generation by a single sex, there spring, two months later, males

and females. These mate; and the same order of things recommences.

To sum up, judging by the three species that form the subject of my

investigations, the Halicti have two generations a year: one in the

spring, issuing from the mothers who have lived through the winter after

being fecundated in the autumn; the other in the summer, the fruit of

parthenogenesis, that is to say, of reproduction by the powers of the

mother alone. Of the union of the two sexes, females alone are born;

parthenogenesis gives birth at the same time to females and males.

When the mother, the original genitrix, has been able once to dispense

with a coadjutor, why does she need one later? What is the puny idler

there for? He was unnecessary. Why does he become necessary now? Shall

we ever obtain a satisfactory answer to the question? It is doubtful.

However, without much hope of succeeding we will one day consult the

Gall-fly, who is better-versed than we in the tangled problem of the

sexes.

INDEX.

Alpine Odynerus.

Amadeus' Eumenes.

Ammophila (see also Hairy Ammophila).

Andrena.

Andrenoid Osmia.

Ant.

Anthidium (see the varieties below, Cotton-bee, Resin Bee).

Anthidium bellicosum.

Anthidium cingulatum (see Girdled Anthidium).

Anthidium diadema (see Diadem Anthidium).

Anthidium florentinum (see Florentine Anthidium).

Anthidium Latreillii (see Latreille's Resin-bee).

Anthidium manicatum (see Manicate Anthidium).

Anthidium quadrilobum (see Four-lobed Resin-bee).

Anthidium scapulare (see Scapular Anthidium).

Anthidium septemdentatum (see Seven-pronged Resin-bee).

Anthocopa papaveris (see Upholsterer-bee).

Anthophora (see also Anthophora of the Walls, Hairy-footed Anthophora,

Masked Anthophora).

Anthophora of the Walls.

Anthophora parietina (see Anthophora of the Walls).

Anthophora pilipes (see Hairy-footed Anthophora).

Anthrax (see Anthrax sinuata).

Anthrax sinuata.

Aphis (see Plant-louse).

Archimedes.

Augustus, the Emperor.

Bee.

Beetle.

Bembex.

Black, Adam and Charles.

Black Plant-louse.

Black Psen.

Black-tipped Leaf-cutter.

Blue Osmia.

Book-louse.

Brown Snail.

Bulimulus radiatus.

Bumble-bee.

Calicurgus (see Pompilus).

Capricorn.

Carpenter-bee.

Cat.

Cemonus unicolor.

Cerambyx (see Capricorn).

Ceratina (see also the varieties below).

Ceratina albilabris.

Ceratina callosa.

Ceratina chalcites.

Ceratina coerulea.

Cerceris.

Cetonia.

Chaffinch.

Chalicodoma (see Mason-bee).

Chrysis flammea.

Cockroach.

Coelyoxis caudata.

Coelyoxis octodentata.

Colletes.

Common Snail.

Common Wasp.

Cotton-bee (see also the varieties of Anthidium).

Crayfish.

Cricket.

Crioceris merdigera (see Lily-beetle).

Cryptus bimaculatus.

Cryptus gyrator.

Cylindrical Halictus.

Darwin, Charles Robert.

Decticus verrucivorus.

Devillario, Henri.

Diadem Anthidium.

Dioxys cincta.

Dog.

Dragon-fly.

Dryden, John.

Dufour, Jean Marie Leon.

Dung-beetle.

Dzierzon, Johann.

Early Halictus.

Earth-worm.

Earwig.

Epeira (see Garden Spider).

Ephialtes divinator.

Ephialtes mediator.

Ephippiger.

Eumenes Amadei (see Amadeus' Eumenes).

Euritema rubicola.

Fabre, Emile, the author's son.

Fabricius, Johann Christian.

Feeble Leaf-cutter.

Field-mouse.

Florentine Anthidium.

Fly (see also House-fly).

Foenus pyrenaicus.

Four-lobed Resin-bee.

Franklin, Benjamin.

Garden Snail.

Garden Spider.

Girdled Anthidium.

Girdled Snail (see Brown Snail).

Gnat.

Golden Osmia.

Goldfinch.

Grasshopper (see also Great Green Grasshopper).

Great Green Grasshopper.

Great Peacock Moth.

Green Grasshopper (see Ephippiger, Great Green Grasshopper).

Green Osmia.

Grey Lizard.

Hairy Ammophila.

Hairy-footed Anthophora.

Halictus (see also the varieties below).

Halictus cylindricus (see Cylindrical Halictus).

Halictus malachurus (see Early Halictus).

Halictus zebrus (see Zebra Halictus).

Hare-footed Leaf-cutter.

Helix algira.

Helix aspersa (see Common Snail).

Helix caespitum (see Garden Snail).

Helix nemoralis.

Helix striata.

Heriades rubicola.

Herring.

Hive-bee.

Honey-bee (see Hive-bee).

Horned Osmia.

House-dog (see Dog).

House-fly.

Kid.

Kirby, William.

La Fontaine, Jean de.

Lamb.

Languedocian Sphex.

Lanius collurio (see Red-backed Shrike).

La Palice, Jacques de Chabannes, Seigneur de.

Latreille, Pierre Andre.

Latreille's Osmia.

Latreille's Resin-bee.

Leaf-cutter, Leaf-cutting Bee (see Megachile).

Leaf-insect.

Leucopsis.

Lily-beetle.

Lithurgus (see also the varieties below).

Lithurgus chrysurus.

Lithurgus cornutus.

Lizard (see also Grey Lizard).

Locust.

Locusta viridissima (see Great Green Grasshopper).

Macmillan Co.

"Mademoiselle Mori", author of.

Manicate Anthidium.

Mantis, Mantis religiosa (see Praying Mantis).

Masked Anthophora.

Mason-bee (see also the varieties below).

Mason-bee of the Pebbles (see Mason-bee of the Walls).

Mason-bee of the Sheds.

Mason-bee of the Shrubs.

Mason-bee of the Walls.

May-fly.

Meade-Waldo, Geoffrey.

Megachile (see also the varieties below).

Megachile albocincta (see White-girdled Leaf-cutter).

Megachile apicalis (see Black-tipped Leaf-cutter).

Megachile argentata (see Silvery Leaf-cutter).

Megachile Dufourii (see Silky Leaf-cutter).

Megachile imbecilla (see Feeble Leaf-cutter).

Megachile lagopoda (see Hare-footed Leaf-cutter).

Megachile sericans (see Silky Leaf-cutter).

Melitta (see Colletes).

Miall, Bernard.

Midwife Toad.

Morawitz' Osmia.

Odynerus (see also the varieties below)

Odynerus alpestris (see Alpine Odynerus).

Odynerus delphinalis.

Odynerus rubicola.

Oil-beetle.

Omalus auratus.

Osmia (see also the varieties below).

Osmia andrenoides (see Andrenoid Osmia).

Osmia aurulenta (see Golden Osmia).

Osmia cornuta (see Horned Osmia).

Osmia cyanea (see Blue Osmia).

Osmia cyanoxantha.

Osmia detrita (see Ragged Osmia).

Osmia Latreillii (see Latreille's Osmia).

Osmia Morawitzi (see Morawitz' Osmia).

Osmia parvula (see Tiny Osmia).

Osmia rufo-hirta (see Red Osmia).

Osmia tricornis (see Three-horned Osmia).

Osmia tridentata (see Three-pronged Osmia).

Osmia versicolor (see Variegated Osmia).

Osmia viridana (see Green Osmia).

Pelopaeus.

Perez, Professor Jean.

Philanthus (see Philanthus apivorus).

Philanthus apivorus.

Plant-louse (see also Black Plant-louse).

Pompilus.

Praying Mantis.

Prosopis confusa.

Psen atratus (see Black Psen).

Rabelais, Francois.

Ragged Osmia.

Reaumur, Rene Antoine Ferchault de.

Red-backed Shrike.

Red-Osmia.

Resin-bee (see also the varieties).

Ringed Calicurgus (see Pompilus).

Rodwell, Miss Frances.

Rosechafer (see Cetonia).

Sapyga (see Spotted Sapyga).

Sardine.

Scapular Anthidium.

Scolia.

Scorpion.

Seven-pronged Resin-bee.

Shrike (see Red-backed Shrike).

Silky Leaf-cutter.

Silvery Leaf-cutter.

Snail (see also the varieties)

Social Wasp (see Common Wasp).

Solenius lapidarius.

Solenius vagus.

Sophocles.

Sparrow.

Spence, William.

Sphex (see also Languedocian Sphex, Yellow-winged Sphex.)

Spotted Sapyga.

Stick-insect.

Stizus.

Tachina.

Tachytes.

Tarantula.

Teixeira de Mattos, Alexander.

Termite.

Three-horned Osmia.

Three-pronged Osmia.

Tiberius, the Emperor.

Tiny Osmia.

Tripoxylon figulus.

Unarmed Zonitis (see Zonitis mutica).

Upholsterer-bee.

Variegated Osmia.

Virgil.

Wasp (see also Common Wasp).

Weaving Spider.

Weevil.

White-girdled Leaf-cutter.

Wolf.

Worm (see Earth-worm).

Xylocopa violacea (see Carpenter-bee).

Yellow-winged Sphex.

Zebra Halictus.

Zonitis mutica.

End of Project Gutenberg's Bramble-bees and Others, by J. Henri Fabre

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