CHAPTER XIV

ARACHNIDA EMBOLOBRANCHIATA (_CONTINUED_)—ARANEAE (_CONTINUED_)

HABITS—ECDYSIS—TREATMENT OF YOUNG—MIGRATION—WEBS—NESTS—EGG-COCOONS—

POISON—FERTILITY—ENEMIES—PROTECTIVE COLORATION—MIMICRY—SENSES—

INTELLIGENCE—MATING HABITS—FOSSIL SPIDERS

EARLY LIFE OF SPIDERS.

=Ecdysis or Moulting.=—Spiders undergo no metamorphosis—that is to say,

no marked change of form takes place, as is so often the case among

Insects, in the period subsequent to the hatching of the egg. This fact,

by the by, is a great trouble to collectors, as it is generally

extremely difficult, and sometimes quite impossible, to identify

immature specimens with certainty.

But although unmistakably a spider as soon as it leaves the egg, the

animal is, at first, in many respects incomplete, and it is only after a

series of moults, usually about nine in number, that it attains its full

perfection of form.

Until the occurrence of its first moult it is incapable of feeding or

spinning, mouth and spinning tubes being clogged by the membrane it then

throws off. It is at first pale-coloured and less thickly clothed with

hairs and spines than it eventually becomes, and the general proportions

of the body and the arrangement of the eyes are by no means those of the

adult in miniature, but will be greatly modified by unequal growth in

various directions. It speedily, however, attains its characteristic

shape and markings, and after one or two ecdyses little alteration is to

be noticed, except increase in size, until the final moult, when the

spider at length becomes sexually mature.

The first moult takes place while the newly-hatched spider is still with

the rest of the brood either in or close to the “cocoon” or egg-bag.

M‘Cook[268] thus describes the conclusion of the operation in the case

of _Agelena naevia_:—

“While it held on to the flossy nest with the two front and third pairs

of legs, the hind pair was drawn up and forward, and the feet grasped

the upper margin of the sac-like shell, which, when first seen, was

about half-way removed from the abdomen. The feet pushed downwards, and

at the same time the abdomen appeared to be pulled upward until the

white pouch was gradually worked off.”

The later moults are generally accomplished by the spider collecting all

its legs together and attaching them with silk to the web above, while

the body, also attached, hangs below. The old skin then splits along the

sides of the body, and the animal, by a series of violent efforts,

wriggles itself free, leaving a complete cast of itself, including the

legs, suspended above it. For a day or two before the operation the

spider eats nothing, and immediately upon its completion it hangs in a

limp and helpless condition for a quarter of an hour or so, until the

new integument has had time to harden. It is not unlikely that the

reader has mistaken these casts for the shrivelled forms of unlucky

spiders, and has had his sympathies aroused, or has experienced a grim

satisfaction, in consequence—an expenditure of emotion which this

account may enable him to economise in future.

Limbs which the animal has accidentally lost are renewed at the time of

moulting, though their substitutes are at first smaller than those they

replace. On the other hand, the struggle to get rid of the old skin

sometimes results in the loss of a limb, and the spider is doomed to

remain short-handed until the next ecdysis.

Until the last moult the generative apertures, which are situated under

the anterior part of the abdomen, are completely sealed up. Their

disclosure is accompanied, in the case of the male, by a remarkable

development of the last joint of each pedipalp, which becomes swollen

and often extremely complicated with bulbs, spines, and bristles. A

mature male spider may at once be distinguished by the consequent

knobbed appearance of its palps; and the particular form they assume is

highly characteristic of the species to which the spider belongs.

The number of moults, and the intervals at which they occur, no doubt

vary with different species. In the case of _Argiope aurelia_,

Pollock[269] has found that the female moults nine times after leaving

the cocoon, the first ecdysis occurring after an interval of from one to

two months, according to the abundance or scarcity of food. The

subsequent intervals gradually increase from about a fortnight to

something over three weeks.

=Behaviour of the Newly-hatched Spider.=—The mode of life of a spider

just freed from the cocoon will of course vary greatly according to the

Family to which it belongs.

The EPEIRIDAE are the builders of the familiar wheel or orb-web. Spiders

of this Family usually remain together on friendly terms for a week or

more after leaving the nest. Most of the time they are congregated in a

ball-like mass, perhaps for the sake of warmth, but upon being touched

or shaken they immediately disperse along the multitudinous fine lines

which they have spun in all directions, to reassemble as soon as the

panic has subsided. Such a ball of the yellow and black offspring of the

large Garden-spider, _Epeira diademata_, is no uncommon sight in the

early autumn, and the shower of “golden rain” that results from their

disturbance is not likely to be forgotten if it has ever been observed

by the reader. This harmonious family life only continues as long as the

young spiders are unable to feed—a period which, in some of the larger

species, is said to extend to ten days or a fortnight.

Individual life then commences, and each member of the dispersed group

sets up housekeeping on its own account, constructing at the first

attempt a snare in all respects similar, except in size, to those of its

parent.

Of course the young Spiders have not migrated far, and a bush may

frequently be seen covered by the often contiguous nets of the members

of a single brood. This, as Dr. M‘Cook thinks, is the true explanation

of some of the cases of “gregarious spiders” which Darwin[270] and other

naturalists have occasionally described, though social spiders exist

(see _Uloborus_, p. 411).

Very similar habits obtain among the THERIDIIDAE, or line-weaving

spiders, a familiar example of which is the pretty little _Theridion

sisyphium_, whose highly-irregular snare may be found on any holly bush

during the summer months.

[Illustration:

FIG. 188.—=A=, _Pardosa_ sp. ♀, with young on the abdomen; =B=, young

_Pardosa_ detached; =C=, outline of the Spider with young removed.

(From the living specimen.)

]

The LYCOSIDAE, or Wolf-spiders, which chase their prey instead of lying

quietly in ambush to ensnare it, are exceedingly interesting in their

treatment of their young. The cocoon, or bag of eggs, is carried about

on all their expeditions, attached beneath the abdomen, or held by the

jaws, and the young spiders, on escaping from it, mount on the mother’s

back, and indulge vicariously in the pleasures of the chase from this

point of vantage. The empty egg-bag is soon discarded, but the brood

continues to ride on the mother’s back for about a week, dismounting

only to follow her as she enters her little silk-lined retreat in the

ground.

During this time they appear to require no food, but they at length

begin to disperse, the mother gently but firmly removing such

individuals as are disposed to trespass upon her maternal solicitude

longer than she considers desirable.

Many young spiders of various Families proceed immediately to seek new

hunting-grounds by the aid of the wind, and become for the time being

diminutive aeronauts. This habit was observed by the earliest British

araneologist, Martin Lister,[271] as long ago as 1670, and has been

alluded to by many writers since his time.

The topmost bar of an iron railing in spring or early autumn will

generally be found peopled with minute spiders, and if the day be fair

and the wind light, the patient observer may be rewarded by a curious

and interesting sight.

The spider seeks the highest spot available, faces the wind, and

straightens its legs and body, standing, so to speak, upon its toes, its

abdomen with its spinning tubes being elevated as much as possible.

Streamers of silk presently appear from the spinnerets and float gently

to leeward on the light current of air. The spider has no power to shoot

out a thread of silk to a distance, but it accomplishes the same result

indirectly by spinning a little sheet or flocculent mass which is borne

away by the breeze.

[Illustration:

FIG. 189.—Young Spider preparing for an aerial voyage. (After

Emerton.)

]

When the streaming threads pull with sufficient force the animal casts

off, seizes them with its legs, and entrusts itself to the air, whose

currents determine the height to which it is carried and the direction

of its journey. The duration, however, is not quite beyond the spider’s

control, at all events in calm weather, for it can furl its sail at

will, hauling in the threads “hand-over-hand,” and rolling them up into

a ball with jaws and palps.

This curious ballooning habit of young Spiders is independent of the

particular family to which they belong, and it is remarkable that

newly-hatched Lycosidae and Aviculariidae, whose adult existence is

spent entirely on or under the ground, should manifest a disposition to

climb any elevated object which is at hand.

The “Gossamer,” which so puzzled our forefathers, is probably no mystery

to the reader. It is, of course, entirely the product of Spider

industry, though not altogether attributable to the habit of ballooning

above described. Only a small proportion of gossamer flakes are found to

contain spiders, though minute insects are constantly to be seen

entangled in them. They are not formed in the air, as was supposed long

after their true origin was known, but the threads emitted by multitudes

of spiders in their various spinning operations have been intermingled

and carried away by light currents of air, and on a still, warm day in

spring or autumn, when the newly-hatched spider-broods swarm, the

atmosphere is often full of them.

They rise to great heights, and may be carried to immense distances.

Martin Lister relates how he one day ascended to the highest accessible

point of York Minster, when the October air teemed with gossamer flakes,

and “could thence discern them yet exceeding high” above him. Gilbert

White describes a shower, at least eight miles in length, in which “on

every side, as the observer turned his eyes, he might behold a continual

succession of fresh flakes falling into his sight, and twinkling like

stars as they turned their sides toward the sun.” The ascent of a hill

300 feet in height did not in the least enable him to escape the shower,

which showed no sign of diminution.

The mortality among very young spiders must be exceedingly great;

indeed, this is indicated by the large number of eggs laid by many

species, an unfailing sign of a small proportion of ultimate survivors.

We shall have, by and by, to speak of some of their natural enemies, but

apart from these their numbers are sadly reduced by the rigours of the

weather, and appreciably also by their tendency to cannibalism. A

thunderstorm will often destroy a whole brood, or they may perish from

hunger in the absence of an adequate supply of insects minute enough for

their small snares and feeble jaws. In the latter case they sometimes

feed for a time on one another, and it is even said that two or three of

a brood may be reared on no other food than their unfortunate

companions.

The large and handsome Garden-spider, _Epeira diademata_, has been

known, when well fed, to construct six cocoons, each containing some

hundreds of eggs, and some species are even more fertile, while their

adult representatives remain stationary, or even diminish in number.

=Spider-Webs.=—Some account has already been given of the external and

internal spinning organs of Spiders. Within the body of the animal the

silk is in the form of a gummy fluid; and this, being emitted in

exceedingly fine streams, solidifies as it meets the air. It cannot be

shot out to any distance, but the animal usually draws it out by its

hind legs, or attaches it to a spot, and moves away by walking or

allowing itself to drop. It has some power of checking the output, and

can stop at will at any point of its descent; but the sphincter muscles

of the apertures are but weak, and by steady winding the writer has

reeled out a hundred yards of the silk, the flow of which was only then

interrupted by the spider rubbing its spinnerets together and breaking

the thread.

There is, of course, no true spinning or interweaving of threads in the

process, but parallel silken lines are produced, varying in number

according to the special purpose for which they are designed, and

sometimes adhering more or less to one another on account of their

viscidity and closeness.

The silk is utilised in many ways, serving for the construction of

snares, nests, and cocoons, as well as for enwrapping the captured prey,

and for anchoring the spider to a spot to which it may wish to return.

Spiders may be roughly distinguished as sedentary or vagabond, the

former constructing snares, and the latter chasing their prey in the

open. We will first consider the various forms of snare, beginning with

that characteristic of the Epeiridae.

=The Circular Snare.=—This familiar object, sometimes spoken of as the

orb-web or wheel-web, is always the work of some spider of the Family

Epeiridae.

The accuracy and regularity of form exhibited by these snares has caused

their architects to be sometimes called the _geometric_ spiders. The

ingenuity displayed by them has always excited the admiration of the

naturalist, and this is increased on closer observation, for the snares

are in reality even more complex than they appear at first sight.

The first care of the spider is to lay down the foundation threads which

are to form the boundary lines of its net. If the animal can reach the

necessary points of attachment by walking along intervening surfaces the

matter is comparatively simple. The spinnerets are separated and rubbed

against one of the points selected, and the spider walks away, trailing

behind it a thread which it keeps free from neighbouring objects by the

action of one of its hind legs. On reaching another desirable point of

attachment the line is made taut and fixed by again rubbing the

spinnerets against it. By a repetition of this proceeding a framework is

presently constructed, within which the wheel or orb will ultimately be

formed.

The process of fixing and drawing out a line can be conveniently watched

in the case of a Spider imprisoned in a glass vessel, and it will be

seen, by the aid of a lens, that a large number of very fine lines

starting from the point of attachment seem to merge into a single line

as the Spider moves away. This has given rise to the prevalent and very

natural idea that the ordinary spider’s line is formed or “woven” of

many strands. This, however, is not the case,[272] for the fine

attachment-lines are not continued into the main thread, but only serve

to anchor it to the starting-point.

As has been said, the spider can throw into play a varying number of

spinning tubes at will, and in point of fact those used in laying down

these foundation-lines are either two or four in number. The spider,

however, often finds it necessary to strengthen such a line by going

over it afresh.

Every one must have noticed that orb-webs frequently bridge over gulfs

that are clearly quite impassable to the spider in the ordinary way.

They often span streams—and Epeirid spiders cannot swim—or they are

stretched between objects unattainable from each other on foot except by

a very long and roundabout journey. When this is the case, the animal

has had recourse to the aid of the wind. A spider of this family placed

on a stick standing upright in a vessel of water is helpless to escape

if the experiment be tried in a room free from draughts. With

air-currents to aid it, silken streamers will at length find their way

across the water and become accidentally entangled in some neighbouring

object. When this has happened, the spider hauls the new line taut, and

tests its strength by gently pulling at it, and if the result is

satisfactory, it proceeds to walk across, hand-over-hand, in an inverted

position, carrying with it a second line to strengthen the first. This

is exactly what happens in nature when a snare is constructed across

chasms otherwise impassable, and it may be imagined that the spider

regards as very valuable landed property the foundation lines of such a

web, for, if destroyed, the direction or absence of the wind might

prevent their renewal for days. They are accordingly made strong by

repeated journeys, and are used as the framework of successive snares,

till accident at length destroys them.

A single line which finds anchorage in this way is sufficient for the

purposes of the spider. It has only to cross over to the new object,

attach a thread to some other point of it, and carry it back across the

bridge to fix it at a convenient spot on the surface which formed the

base of its operations. Between two such bridge-lines the circular snare

is constructed in a manner to be presently described. Sometimes the

tentative threads emitted by the spider travel far before finding

attachment. In the case of the English _Epeira diademata_ the writer has

measured bridge-lines of eleven feet in length; and with the great

Orb-weavers of tropical countries they frequently span streams several

yards in width.

Two stout bridge-lines thus constructed will form the upper and lower

boundaries of the net. The lateral limits are easily formed by cross

lines between them at a convenient distance apart. The spider chooses a

point, say, on the upper bridge-line, fixes its thread there, and

carries it round to the lower line, where it is hauled taut and firmly

attached. Two such cross lines give, with the bridge-lines, an irregular

four-sided figure within which to stretch the snare, and now the work is

perfectly straightforward, and can proceed without interruption.

Attention is first paid to the radii of the circular web. The first

radii are formed by drawing cross lines within the framework in the same

manner as before, but the spider carefully attaches these where they

intersect by a small flossy mass of silk, and this central point or hub

becomes the basis of its subsequent operations. It is a simple matter to

add new radial lines by walking from the centre along one of those

already formed and fixing the thread to some new point of the

circumference. They are not laid down in any invariable order, but with

a kind of alternation which has the general effect of keeping the strain

on every side fairly equal. Almost every time the spider reaches the

centre it slowly revolves, uniting the radii afresh at their point of

junction, and increasing the strength and complexity of the hub. It also

occasionally digresses so far as to stretch the whole structure by

bracing the framework at additional points, so that it loses its

four-sided form and becomes polygonal. We have now a number of spokes

connecting a central hub with an irregular circumference.

The hub is next surrounded by what Dr. M‘Cook calls a “notched zone,”

consisting of a few turns of spiral thread which serve to bind more

firmly the spokes of the wheel. The most important part of the work is

still to be performed. The lines hitherto laid down are perfectly dry

and free from viscidity, so that an entangled insect would easily be

able to free itself. A viscid spiral line remains to be spun, and the

snare will be complete. The precise method of laying this down will vary

somewhat according to the species, but, to refer again to the large

Garden-spider, the proceeding is as follows:—Commencing at a point

somewhat outside the notched zone, the creature rapidly works in a

spiral thread of ordinary silk with the successive turns rather far

apart. This forms a kind of scaffolding, by clinging to which the spider

can put in the viscid spiral, which it commences at the _circumference_.

Its action now becomes exceedingly careful and deliberate, though by no

means slow, and so great is its absorption in the work that it may be

observed quite closely with a hand-lens without fear of interrupting it.

The proceeding consists in drawing out from its spinnerets with one (or

both) of its hind legs successive lengths of a highly elastic line,

which it stretches just at the moment of fixing it to a radius, and then

lets go with a snap. There is no hesitation or pause for consideration,

but there is a peculiar deliberateness in drawing out each length of the

thread which, together with stretching and sudden release, require

explanation. Now, it has already been mentioned that the framework and

radii of the snare are not at all moist or adhesive. This, however, is

not the case with the spiral, upon which the spider chiefly relies in

capturing its prey. A close examination of it—even with the naked eye—

will show it to be beaded over with little viscid globules which, under

a low magnifying power, are seen to be arranged with remarkable

regularity.

[Illustration:

FIG. 190.—=A=, =B=, =C=, =D=, Stages in the formation of the viscid

globules of the web.

]

A very convenient method of investigation is to carry off a

newly-constructed web—or, better still, one not quite finished—on a

piece of plate glass, to which it will adhere by reason of the viscid

spiral, and on which it may be examined at leisure. Immersion in a

staining fluid will colour the viscid spiral, and show its structure in

a striking manner. It will appear to consist of a thread strung with

beads of two sizes, occurring with pretty uniform alternation, though

two of the larger beads are often separated by two or more of the

smaller.

Until recently it was supposed that the deposition of these beads upon

the spiral line was a subsequent operation, and, in view of their vast

numbers and regularity, the circumstance naturally excited great wonder

and admiration. Blackwall[273] estimated that, in a fourteen-inch net of

_Epeira cornuta_, there were at least 120,000 viscid globules, and yet

he found that its construction occupied only about forty minutes! The

feat, from his point of view, must be allowed to be rather startling.

As a matter of fact, the thread, on being slowly drawn out, is uniformly

coated with viscid matter which _afterwards_ arranges itself into beads,

the change being assisted by the sudden liberation of the stretched

line.

Boys[274] has shown their formation to be quite mechanical, and has

obtained an exact imitation of them by smearing with oil a fine thread

ingeniously drawn out from molten quartz. The oil arranged itself into

globules exactly resembling the viscid “beads” on the spider’s line. If

the web be carried bodily away on a sheet of glass, as above described,

while the spider is engaged upon the spiral line, the experimenter will

have permanent evidence of the manner in which the globules are formed.

The last part of the line will be quite free from them, but uniformly

viscid. Tracing it backwards, however, the beads are soon found, at

first irregularly, but soon with their usual uniformity. The thread

which the spider has thus “limed” for the capture of prey is really

two-stranded—the strands not being twisted, but lying side by side, and

glued together by their viscid envelope.

The snare is now practically complete, and the proprietor takes up her

position either in the centre thereof, or in some retreat close at hand,

and connected with the hub by special lines diverging somewhat from the

plane of the web. Notwithstanding the possession of eight eyes—which, in

sedentary spiders, are by no means sharp-sighted—it is mainly by the

sense of touch that the spider presently becomes aware that an insect is

struggling in the net. She immediately rushes to the spot, and suits her

action to the emergency.

If the intruder is small, it is at once seized, enveloped in a band of

silken threads drawn out from the spinnerets, and carried off to the

retreat, to be feasted on at leisure. If it seems formidable it is

approached carefully—especially if armed with a sting—and silk is deftly

thrown over it from a safe distance till it is thoroughly entangled, and

can be seized in safety by the venomous jaws of its captor. Sometimes

the insect is so powerful, or the spider so sated with food, that the

latter hastens to set free the intruder by biting away the threads which

entangle it before much havoc has been wrought with the net.

The viscid matter on the spiral line dries up after some hours, so that,

even if the web has not been destroyed by insects and stress of weather,

this portion of it must be frequently renewed. Commencing a new web is,

as has been seen, a troublesome matter, and it will readily be

understood that the spider prefers, where practicable, to patch up the

old one. This is done by biting away torn and ragged portions and

inserting new lines in their place.

The part played by the various spinning glands in the construction of

the orb-web may be briefly stated.[275] The ampullaceal glands furnish

the silk for the foundation lines and radii. The spiral has a double

ground-line proceeding from the middle spinnerets, but it is not quite

certain whether it proceeds from the ampullaceal or the tubuliform

glands. The chief function of the latter, in the female, is to furnish

silk for the egg-cocoon. The viscid globules are the products of the

aggregate glands. The aciniform and piriform glands provide the

multitudinous threads by which the spider anchors its various lines and

enwraps its prey.

Some Orb-weavers always decorate their snares with patches or tufts of

flossy silk. In the snare of the North American _Argiope cophinaria_ the

hub is sheeted, and from it extends downwards a zigzag ribbon of silk

stretched between two consecutive radii. Vinson[276] discovered a

remarkable use for similar zigzag bands in the web of the Mauritian

spider, _Epeira mauritia_. It furnished a reserve supply of silk for

enveloping partly entangled insects whose struggles were too vigorous to

succumb to the rather feeble threads which the spider was able to emit

at the moment of capture. The spider was able to overcome a grasshopper

much more powerful than itself by dexterously throwing over it with one

of its hind legs a portion of the ribbon of silk which it had thus

stored up for emergencies.

[Illustration:

FIG. 191.—=A=, Snare of _Hyptiotes cavatus_; =B=, enlarged view of the

Spider, showing the “slack” of the hauled-in line. (After Emerton.)

]

Many orb-webs are defective, a sector of the circle being uniformly

omitted in the structure. The genus _Hyptiotes_ does not belong to the

Epeiridae but to the cribellate Uloboridae, but its defective orb-web is

so curious that it deserves a special mention. A single foundation-line

is laid down, and from it four radii are drawn and are connected with

cross lines, the snare constituting about one-sixth of a circle. From

the centre of the incomplete circle a thread proceeds to some more or

less distant object, and on this the spider takes up its position,

inverted, and hauls in the line till the snare is taut. When the

trembling of the line shows the spider that an insect has struck the

net, it lets go with its fore-legs, and the web, springing back to its

normal position, entangles the intruder more thoroughly by its

vibrations. When large insects are in question the spider has been

observed to “spring” the net several times in succession. _H. cavatus_

is common in the pine woods of Pennsylvania, but the only English

species, _H. paradoxus_, is extremely rare.

A remarkable spider has been discovered in Texas by M‘Cook, which, after

building a horizontal orb-web, converts it subsequently into a dome

(Fig. 192) of exceedingly perfect form. It is named _Epeira basilica_,

and has been the object of careful study by Dr. Marx, who observed the

whole process of web-construction. Threads are attached at various

points on the upper surface of the horizontal wheel, the central portion

of which is gradually pulled up until the height of the dome is nearly

equal to the diameter of its base. But the snare of this spider does not

consist of the dome alone. A sheet of irregular lines is stretched

below, while above there is a maze of threads in the form of a pyramid.

Several other Orb-weavers, as, for instance, _E. labyrinthea_ and _E.

triaranea_, supplement their typical webs by an irregular structure of

silk, and thus form connecting links, as regards habit, between the

group of which we have been speaking and the Theridiidae or

Line-weavers, which may now briefly be dealt with.

[Illustration:

FIG. 192.—Snare of _Epeira basilica_. (After M‘Cook.)

]

=The Irregular Snare.=—The great majority of British Spiders belong to

the family of the Theridiidae, or Line-weavers. Some of these are among

the handsomest of our native species, and are in other respects highly

interesting, but their snares lack the definiteness of structure

exhibited by the orb-web, and little need be said about them.

For the most part they consist of fine irregular lines running in all

directions between the twigs of bushes or among the stems of grass and

herbage. One large and important genus, _Linyphia_, always constructs a

horizontal sheet of irregular threads with a maze of silk above it. Such

snares may be seen in myriads in the wayside hedges during the summer,

and they are especially notable objects when heavily laden with dew.

Insects impeded in their flight by the maze of threads drop into the

underlying sheet, and are soon completely entangled. The spider usually

runs _beneath_ the sheet in an inverted position.

The sheet or hammock of silk is absent in the case of most of the other

genera of this family, their snares being innocent of any definite

method in their structure. They are frequently quite contiguous, and it

is no uncommon thing to find a holly bush completely covered with a

continuous network of threads, the work of a whole colony of the pretty

little spider _Theridion sisyphium_.

As might be imagined from the simplicity or absence of design in the

structure of the net, there appears to be very little complexity in the

nature of the silk used. It is interesting, however, to find that viscid

globules, not unlike those which stud the “spiral line” of the

Epeiridae, are sometimes present in the snares of the Line-weavers,[277]

and in these, too, aggregate glands are present. There is a large spider

of this family, _Theridion tepidariorum_, which may be found to a

certainty in almost any hothouse in this country. In its snare, which is

of the ordinary irregular type, F. Pickard-Cambridge has observed little

patches of flocculent silk, calculated to render more certain the

entanglement of prey, and he has further described a curious comb-like

structure on the hind leg of the animal which is probably used in the

production of this phenomenon. It is by no means unlikely that a more

careful study of these apparently simple snares will lead to the

discovery of further complexity of structure.

[Illustration:

FIG. 193.—Snare of _Uloborus_ sp., some of the lines being thickened

with threads from the cribellum. (After M‘Cook.)

]

_Uloborus_, a cribellate genus which has an Epeirid-like, orbicular

snare, decorates some of the lines with the produce of the cribellate

glands, but viscid globules are absent.

=Sheet-Webs.=—The webs which are such familiar—and, by association,

unpleasant—objects in unused rooms and outhouses are usually the work of

spiders belonging to the Agelenidae and the Dictynidae. To the first

belongs the common House-spider, _Tegenaria civilis_, and its larger

congener, _T. parietina_. These spiders are not attractive in

appearance, and the last-named species especially, with the four-inch

span of its outstretched legs, is a formidable object, and a terror to

domestic servants. An obscure tradition connecting it with Cardinal

Wolsey and Hampton Court has caused it to be known as the Cardinal

Spider. An out-door example of the Agelenidae is the very abundant

_Agelena labyrinthica_, whose sheet-web, with its tubular retreat, is to

be sought on the banks of ditches, or in the hedges of our country

lanes.

The snares of these spiders are exceedingly closely woven of very fine

silk, and take a long time to complete. The process of their

construction may be watched by keeping an _Agelena labyrinthica_

confined in a box with a glass front, and the web, kept free from dust,

is a beautiful object, as its fine texture gradually becomes visible as

a delicate transparent film which develops by imperceptible stages into

an opaque white sheet. The excessive fineness of the silk makes it

difficult at first to see what is taking place. The animal is seen to be

busily moving about, but the result of its labours only gradually

becomes visible. A few delicate foundation-lines are first stretched

across the compartment in which it is confined, and upon these the

spider walks to and fro incessantly with a serpentine motion, and by and

by a muslin-like floor of silk comes into view.

An examination of the spinnerets throws some light upon the operation.

The posterior pair are very long and mobile, and the hair-like

spinning-tubes are distributed on their under surface. The cephalothorax

and abdomen are far more rigidly connected in _Agelena_ than in the

Orb-weavers, but its length of leg and the length and mobility of its

posterior spinnerets enable it to give a wide lateral sweep as it walks

along, strewing fine silken threads upon the foundation-lines already

laid down. Some hours elapse before even a moderately stout web is

constructed, and for long afterwards the spider devotes odd moments of

leisure in going over the ground again and strewing new silk upon the

gradually thickening web. At one corner a silken tube of similar

structure is formed, and in this the spider awaits the advent of any

insect which may alight upon the sheet, when it immediately rushes forth

and seizes it.

The webs of the Dictynidae are very similar in general appearance to

those of the Agelenidae, consisting of a closely-woven sheet with a

tubular nest. They are to be found, moreover, in similar situations,

stretching across the angles of walls in cellars or outhouses, though

some species prefer an out-door existence. Crannies in rock form

convenient sites for such snares, but the family is not without its

representatives in still more open situations. The web, though so

similar to that of _Agelena_, is, however, constructed in a different

manner. In the Dictynidae neither the legs nor the spinnerets are

unusually long, and they do not strew the foundation-lines by a swinging

motion of the body, but the operation is effected by a special

apparatus. These spiders are _cribellate_, and in front of the six

ordinary spinnerets there are a pair of perforated plates connected with

a large number of additional minute spinning glands (see Fig. 182, p.

326). In conjunction with this, the female possesses on the last joint

but one of each hind leg a curious comb-like arrangement of spines, the

“calamistrum.” The animal constructs a sort of skeleton web by means of

its ordinary spinnerets, and when this is completed it combs out silk

from the cribellum by means of the calamistrum, using each hind leg

alternately, and distributes it with a curling motion upon the

scaffolding prepared for it, a nearly opaque web being the result. The

silk from the cribellum is of an adhesive nature, and renders escape

from the web very difficult.

=Spiders’ Nests and Retreats.=—All Spiders construct some description of

nest, and often display great ingenuity in building them. Perhaps none

are more curious than those of the burrowing Aviculariidae, a family

which includes the interesting “Trap-door Spiders.” They are nocturnal

in their habits, about which, consequently, little is known, but their

nests have been carefully studied, especially by Moggridge, who found

them in considerable abundance in various districts of the Riviera.

The jaws of these spiders are especially adapted for digging, and with

them a hole is excavated in the ground to the depth of several inches,

and wide enough to allow the animal to turn. This is carefully lined

with silk which the spider throws against the sides from its long and

upturned posterior spinnerets. But the _chef d’œuvre_ of the whole

structure is a lid or door which protects the entrance to the tube.

There are two types of door which find favour with different species—the

wafer and the cork type, as Moggridge has named them. The former

consists of a thin circular or oval sheet of silk which flaps down

loosely over the tube-entrance, with which it is connected by a

hinge-like attachment. A trap-door of the cork type is a more

complicated structure, being of considerable thickness and having a

bevelled edge, so that it fits into the tube like a plug. Like the wafer

door, it possesses a silken hinge.

To form the wafer door, the spider covers the entrance to the tube with

a closely-woven layer of silk, which it afterwards bites away at the

edge, except at the point where the hinge is to be. Doors of the cork

type consist of alternate layers of silk and earth. After weaving a

covering of silk, the creature brings earth in its jaws and lays it on

the top, binding it down with a second layer of silk, and the process is

repeated until the requisite thickness is attained.

The nests are exceedingly difficult to detect, as the spiders take the

precaution of attaching leaves, moss, or small twigs to the outer

surface of the doors. This does not appear to be the result of

intelligence, but a mere instinctive habit; for if a door be removed and

the surrounding earth denuded of moss, the spider will render the new

door conspicuous by bringing moss from a distance, and thus making a

green spot in the bare patch of earth.[278]

The cork doors fit with great exactness, and there is always to be found

on their under surface a notch by which they are held down by the

fore-legs of the spider against any attempt to open them from without.

Many nests with trap-doors of the wafer type are found to have a second

and more solid door within the tube. This serves to shut off the lower

part of the nest as a still more secure retreat. This second door opens

downwards, and the Spider, getting beneath it, is effectually shielded

from an enemy which may have mastered the secret of the outer barrier.

The nests of some species present still further complications in the way

of lateral branches from the main tube. In one case (_Nemesia congener_)

the burrow becomes =Y=-shaped, and the second door hangs at the fork of

the =Y= in such a manner as to connect the bottom chamber either with

the entrance or with the branch, which does not reach the surface, but

ends blindly.

Trap-door Spiders are greatly attached to their tubes, which they

enlarge and repair at need. They begin burrowing very early in life, and

their tiny tubes resemble in all respects those of their parents. Their

habits are nocturnal, and little is known of them; an observation,

however, on a species inhabiting the island of Tinos in the Grecian

Archipelago (_Cteniza ariana_), by Erber,[279] must not be omitted. This

spider leaves its tube at night and spins a web near at hand and close

to the ground. It carries captured insects into its tube, and in the

morning clears away the net, adding the material of it, M. Erber

believes, to the trap-door.

No true trap-door Spider has as yet been found in this country, but the

allied Atypidae are represented by at least one species, _Atypus

affinis_, which has been discovered in colonies in some localities in

the south of England, notably near Ventnor in the Isle of Wight, and on

Bloxworth Heath in Dorsetshire. This spider, like its continental

cousins, excavates a hole in the earth, generally near the edge of a

heathery bank, and lines it with a tube of silk of such firm texture

that it may be removed intact from the earth in which it is embedded.

The silken tube projects some two inches above the ground, either erect

among the roots of the heather, or lying loosely upon the surface. Its

extremity is always found to be closed, whether from its own elasticity

or by the deliberate act of the proprietor is uncertain, and it seems

probable that the animal spends almost the whole of its existence in the

tube. Simon believes that it feeds almost entirely upon earth-worms

which burrow into its vicinity, and which it, therefore, need not leave

its nest to catch; but the remains of beetles and earwigs have been

found in the tubes at Ventnor.

[Illustration:

FIG. 194.—Funnel of _Cyrtauchenius elongatus_. (After M‘Cook.)

]

This description of nest seems common to all species of the genus

_Atypus_. The American “Purse-web Spider,” _A. abboti_, burrows at the

foot of a tree, against the trunk of which it rears the projecting

portion of its silken tube. At the bottom of the nest the cavity is

enlarged, and blind processes project in different directions.

Another burrowing spider, _Cyrtauchenius elongatus_, surmounts its

silk-lined burrow by a funnel-shaped structure of pure white silk, about

three inches in height and two or three inches in width. There is no

attempt at concealment, and the white funnels are conspicuous among the

thin grass, presenting the appearance of fungi.

The burrowing habit is also common to the Wolf-spiders or Lycosidae, but

beyond a very slight lining of silk there is usually little spinning

work about their nests. Occasionally there is a certain amount of

superstructure in the shape of a silken funnel (_Lycosa tigrina_,

M‘Cook), or of an agglomeration of twigs and pebbles, as in the case of

the “Turret-spider” (_Lycosa arenicola_, Scudder).

[Illustration:

FIG. 195.—Turret of _Lycosa carolinensis_. (After M‘Cook.)

]

A colony of our handsome species, _Lycosa picta_, is an interesting

sight to watch. Their favourite habitat is a sandy soil, variegated with

many-coloured patches of moss and lichen, among which their own markings

are calculated to render them inconspicuous. The observer, by lying

perfectly still, may see them silently stealing forth from their burrows

in the bright sunshine, and hunting diligently in the neighbourhood,

ready to dart back on the faintest alarm, or if the sun should be

temporarily obscured by a passing cloud. So closely do they resemble

their surroundings, that it is only when in motion that they can readily

be detected. It is very curious to see them popping out their heads to

ascertain that the coast is clear before venturing forth, and the utter

silence of their operations adds to the eeriness of the effect. The

tubes of these spiders, though without a trap-door, and only slightly

lined with silk, are =Y=-shaped like those of _Nemesia congener_, the

main tunnel giving off a blind branch about half-way down.

The nest of the Water-spider, _Argyroneta aquatica_, must not be passed

over without mention. This spider, though strictly an air-breathing

animal, spends almost the whole of its existence beneath the water. That

it can live in such a medium is due to the fact that the long hairs

which clothe its abdomen retain a bubble of air as it swims beneath the

water, so that it carries with it its own atmosphere. The air-bubble

which invests its body gives it a strong resemblance to a globule of

quicksilver, and renders it a pretty object in an aquarium as it swims

about in search of food or in prosecution of its spinning operations.

Of these the most interesting is the building of its nest. Working

upon a water plant some distance below the surface, it forms a silken

dome of closely-woven threads, which it next proceeds to fill with

air. To do this the spider rises in the water, raises its abdomen

above the surface, and jerks it down again quickly, so as to carry

with it a bubble of air which it helps to retain with its hind legs.

With this it swims back to its tent, into which it allows the

imprisoned air-globules to escape. By degrees the dome or bell is

filled, and the creature has a dry and snug retreat beneath the water.

In this it passes the winter in a torpid condition. The young of this

species appear to be fond of utilising the empty shells of

water-snails, which they float by filling them with air, and thus save

themselves the trouble of nest-construction.

[Illustration:

FIG. 196.—Egg-cocoons. =A=, _Epeira diademata_, nat. size. =B=,

_Theridion pallens_ × 4, attached to a leaf. =C=, _Agroeca brunnea_,

nat. size, attached to a weed, and not yet coated with mud. =D=,

_Ero furcata_ × 4, attached to a log.

]

=Cocoon.=—The last important spinning operation which remains to be

described is the building of the so-called cocoon. This must be

distinguished from the cocoon of insects, which is a protective covering

of silk within which the larva assumes the pupa form. In the case of the

Spider, the term is applied to the structure which serves to protect and

conceal the eggs. It is often of considerable complexity, and is highly

characteristic of the particular species which constructs it.

All egg-bags are commenced in very much the same way. A small sheet of

silk is woven, and against this, sometimes upon the upper and sometimes

on the under surface, the eggs are deposited, and then covered in with a

second silken layer. The compact silk-covered ball of eggs is then, in

many cases, enclosed in a small compartment which the spider builds with

infinite care and unfailing uniformity, after the pattern peculiar to

its kind. A considerable number of the Orb-weavers are content with a

simple silken case closely investing the eggs, and by its thickness and

the non-conducting quality of the material, sufficient protection is

afforded against inclement weather.

The egg-bag of the large Garden-spider (_E. diademata_) may be

recognised by its great size and its yellow colour, which is deepened by

the still more yellow tint of the eggs within. Those of _Zilla x-notata_

and of many other English Epeirids are of similar structure, but of

white silk. The mother generally avails herself of some natural shelter,

hiding her cocoon beneath loose bark, in the crannies of masonry, or

under the copings of walls.

Many species, on the contrary, boldly expose their cocoons in their

snares, sometimes as many as fourteen being constructed in succession

and strung in a chain. The American species _Epeira caudata_ and _E.

bifurca_ are good examples of this habit, stringing a chain of

characteristic cocoons upon the line connecting the retreat with the

web.

The sedentary Theridiid spiders usually suspend their cocoons in the

neighbourhood of their irregular snares. The green cocoon of _Theridion

sisyphium_ is generally more or less concealed by an accumulation of

débris. The minute species _T. pallens_ constructs a cocoon of peculiar

shape on the under surface of a leaf (Fig. 196, B). It is a conical

structure of white silk, considerably larger than the spider itself,

attached at its broad end,[280] and having several curious lateral

projections near the middle.

Among the Lycosidae or “Wolf-spiders” the prevailing habit of the mother

is to carry the egg-bag attached beneath her abdomen upon all her

hunting excursions. It is spheroidal in shape, made up of an upper and a

lower half, with a seam-like junction at the equator, so to speak. The

lower half is first woven, and the eggs are deposited within it. The

upper hemisphere is then spun, and the edges gathered in and finished

off, the seam or suture being always discernible. The bag is now

attached by silken threads to the spinnerets, and bumps merrily over the

ground as the animal hurries along in search of prey. If deprived of it

she evinces the greatest distress, and frequently will not try to escape

without it.

=Attempts to utilise Spider Silk.=—It is long since the web of the

House-spider, taken internally, was considered a specific for the ague,

though its value as a styptic has been recognised in quite recent times.

It is, however, with other uses of Spider silk that we are here

concerned.

Spider silk has been extensively used in the micrometer eyepieces of

telescopes where very fine intersecting lines are required. For this

purpose the radial or scaffolding lines of the circular snare were

selected, the spiral being unsuited on account of its row of viscid

beads. Professor C. V. Boys has, however, discovered in his quartz

fibres a material better adapted for this purpose.

Several attempts have been made to weave the silk of Spiders as a

substitute for that of the silk-worm. Web silk is, of course, far too

fine to furnish a durable material, but the cocoons are usually formed

of coarser silk, and it is with them that the experiment has been tried.

About the beginning of the eighteenth century certain stockings and

mittens made of Spider silk from the cocoons of _Epeira diademata_, by

M. Bon of Languedoc, attracted so much attention that the Academy

desired M. Réaumur to investigate the matter. His report was

unfavourable to the commercial utility of Spider silk. The cocoon

threads, though eighteen times stronger than those of the web, were but

one-fifth of the strength of those obtained from the silk-worm, and the

lustre was inferior. A still more fatal objection, however, was founded

upon the cannibalistic habits of the spider, and the difficulty of

furnishing it with acceptable food.

M. Vinson has recorded that some of the spiders of Madagascar,

especially _Epeira madagascarensis_, are far better adapted than any of

our English species to a commercial use. They furnish silk of a

beautiful clear yellow colour; they are accustomed to live harmoniously

together in families; and the range of climate in which they can thrive

is very considerable. The Creole ladies of this island, under the

administration of General Decaen, wove a magnificent pair of gloves from

spider silk, with their own hands, for presentation to the French

Empress.

=Poison of Spiders.=—All spiders possess poison-glands, which have their

openings on the fangs of the chelicerae. The action of the chelicera in

striking does not express the venom, but the poison-bag itself is

covered with a muscular coat by which the contained fluid is expelled.

It is highly probable, therefore, that the venom is under the control of

the animal’s will, and is economised when the simple wound is sufficient

for the purpose—a supposition which may partially explain the very

divergent opinions held with regard to the effect of the spider’s bite.

The reputation of the “Tarantula” Spider is well known, but what

particular species, if any, was intended by the name is quite uncertain.

The name is derived from the town Tarentum, and was certainly applied to

a Lycosid spider. Probably the common south European species, _Lycosa

narbonensis_, has as good a claim to the honour as any. The confusion

has been increased by extending the name to spiders of quite a different

family. _Eurypelma hentzii_, one of the Aviculariidae, is commonly known

as the Tarantula in America.

The superstition of the tarantula dance is well known. The bite of the

spider was supposed to induce a species of madness which found its

expression—and its cure—in frantic and extravagant contortions of the

body. If the dance was not sufficiently frenzied, death ensued. In the

case of survivors, the symptoms were said to recur on the anniversary of

the bite. Particular descriptions of music were supposed to incite the

patient to the excessive exertion necessary for his relief; hence the

“Tarantella.”

In the Middle Ages epidemics of “tarantism” were of frequent occurrence,

and spread with alarming rapidity. They were seizures of an hysterical

character, analogous to the ancient Bacchic dances, and quite

unconnected with the venom of the spider from which they took their

name. The condition of exaltation and frenzy was contagious, and would

run through whole districts, with its subsequent relapse to a state of

utter prostration and exhaustion. The evil reputation of the Tarantula

appears to have exceedingly little basis in fact.

Baglivi relates how the country people capture the Tarantula by

imitating the buzzing of an insect at the mouth of its hole. “_Quo

audito, ferox exit Tarentula ut muscas, quorum murmur esse putat,

captet; captatur tamen a rustico insidiatore._”

Fabre[281] acted the part of the “insidious rustic” with slight success;

but by other stratagems he enticed the creatures from their holes, and

made some interesting observations upon the effects of their bite. He

found that bees and wasps were instantaneously killed by them. This

immediately fatal effect he found to be due to the fact that the spider

invariably struck the insect in a particular spot, at the junction of

the head with the thorax. Bees must often wander into Tarantula’s holes,

and a prolonged contest, though it might end in the death of the insect,

would be certain also to result fatally for the spider. It has,

therefore, acquired the habit of striking its foe in the one spot which

causes instant death. When Fabre presented a bee to a Tarantula in such

a manner that it was bitten in some other region, the insect survived

several hours.

A young sparrow, just ready to leave the nest, was bitten in the leg.

The wound became inflamed, and the limb appeared to be paralysed, but

the victim did not at first suffer in general health, and fed heartily;

death resulted, however, on the third day. A mole died in thirty-six

hours after the bite.

From these experiments, Fabre came to the conclusion that the venom of

the Tarantula was at all events too powerful to be entirely negligible

by man.

[Illustration:

FIG. 197.—_Latrodectus mactans_, ♂, natural size.

]

Trifling causes may have a fatal effect upon a man in ill health, and it

is quite possible that death has sometimes resulted from the Tarantula’s

bite. Its effect upon a healthy subject, however, is certainly not

serious. Goldsmith, in his _Animated Nature_, entirely discredits the

current stories about this animal, saying that the Italian peasants

impose upon credulous travellers by allowing themselves, for money, to

be bitten by the Tarantula, and then feigning all the symptoms which are

traditionally supposed to ensue.

There is a genus of the Theridiidae, by name _Latrodectus_, whose

poisonous reputation almost rivals that of the Tarantula. It is

remarkable, moreover, that it is regarded as particularly dangerous in

such widely separated portions of the world as Madagascar, New Zealand,

Algeria, the West Indies, and North America. These spiders, strangely

enough, are by no means particularly large or formidable in appearance.

There are two species in Madagascar, known to the natives by the names

of _Mena-vodi_ and _Vancoho_. Vinson[282] describes the terror which is

locally inspired by the first-named species, whose bite is believed to

be fatal unless measures are promptly taken to counteract the poison.

They sometimes cauterise the wound, but the usual treatment consists in

inducing profuse perspiration—a method of cure which recalls the

Tarantula dance of Southern Europe. Flacourt[283] mentions the _Vancoho_

as the most dangerous animal of Madagascar, and more formidable than the

scorpion. He relates cases among his own negroes where the bite was

followed by a condition of syncope which lasted two days.

A New Zealand species is known by the natives as the _Katipo_. It is of

about the size of a pea, and almost black in colour. Mr. Meek of Waiwera

gives a most circumstantial account of the effect of its bite upon his

son.[284] During the four days which followed the bite he suffered

excruciating pain, which spread from his leg to the spine, arms, and

chest, and he lost twelve pounds in weight. Relief was obtained by

frequent doses of brandy and the use of a liniment.

The natives of New Zealand have a great horror of this spider, but hold

the curious belief that its death will ensure the cure of any one it may

have bitten. If unable to find it, they will burn the house down rather

than allow it to escape. Their dread, however, is confined to a variety

which lives among the sedge of the sea-beach, and they carefully avoid

sleeping in such places.

Two of the best authenticated cases of serious results ensuing from the

bite of a spider of this genus come from North Carolina.[285]

A farm labourer in the employ of Mr. John Dick of Greensborough was

bitten by _Latrodectus mactans_ about half-past eight in the morning,

and died between ten and eleven o’clock at night. Small pimples were

raised in the neighbourhood of the bite, but no puncture was

discernible. Intermittent pains and spasms ended in a comatose condition

from which he did not rally. The man appeared previously to be in

perfect health.

Another man on Mr. Dick’s farm was bitten by the same species of spider.

He resumed work, but a spasm of pain caused him to mount his horse and

endeavour to ride home, but he fell off, and lay in a state of

unconsciousness. He was found in this condition by a fellow-workman, and

taken home. Large quantities of whisky were administered without any

intoxicating effect, and this afforded some relief from the

constantly-recurring spasms. The paroxysms continued for three weeks,

and two months elapsed before he was able to resume work. On the ankle

where he was bitten pimples appeared as in the previous case, and these

broke out again, long after the occurrence, whenever he became

overheated in his work.

These accounts are sufficiently circumstantial and well authenticated,

but the fact of the actual bite depends upon the statement of the

victims alone, and they may possibly have mistaken the cause of their

trouble.

Southern Europe possesses a congener of this spider in _Latrodectus

13–guttatus_, the well-known “Malmignatte,” which is also considered

extremely poisonous. The Royal Academy of Medicine and Surgery at

Barcelona appointed Dr. Graells, in 1833, to inquire into the effects of

the bite of this spider, cases of which had become exceedingly frequent.

He found a curious correspondence between the frequency of these cases

and the advent of migratory locusts, which the spider successfully

attacked. In his report[286] he details the symptoms in certain

unquestionably authentic cases. There was a double puncture, surrounded

by red circles, the region of the wound afterwards swelling greatly. The

pain and swelling extended over the whole limb, and often to the body,

and convulsions occurred, followed by great prostration and collapse.

All the patients eventually recovered, their cure being heralded by

profuse perspiration.

It must be mentioned, however, that the eminent Arachnologist M. Lucas

states that he has several times allowed himself to be bitten by this

identical spider without any ill effects.

The testimony is thus conflicting in this case also. It is impossible,

however, to believe that there is no basis in fact for the poisonous

reputation of a comparatively insignificant-looking spider in so many

widely separated parts of the world, supported as it is by certain

well-substantiated cases. The variable effects of its bite may find a

partial explanation in a variation in the strength of its venom at

different seasons, and it has already been mentioned that the injection

of poison into its victim is a voluntary act, and does not necessarily

accompany its bite. Among the species regarded as especially venomous

must be mentioned _Phidippus morsitans_, one of the larger of the

Attidae.

It is exceedingly likely that the bite of the large tropical

Aviculariidae is really formidable. They appear, however, more anxious

to escape than to show fight, and we possess little reliable information

with regard to them. Doleschall shut up small birds with two West Indian

species, and death followed their bite almost immediately. Ten days’

starvation appeared to weaken the venom, for a bird bitten by a spider

fasting for that period recovered after an indisposition of six hours.

Most Arachnologists have recorded experiments with regard to the venom

of the commoner European species, with equally conflicting results.

Blackwall came to the conclusion that loss of blood, and not poison,

caused the death of spider-bitten insects. He could not himself

distinguish a spider bite from the prick of a needle inflicted upon his

hand at the same time. Bees, wasps, and grasshoppers survived the bite

about as long as other insects of the same species outlived a

needle-prick in the same part of the body. Walckenaer’s experience was

of the same nature. Bertkau, however, when bitten in the hand, felt

clear indications of an irritant poison in the wound. The hairs of some

of the large hairy species of the Aviculariidae possess poisonous

properties. They are readily parted with, and when the animal is touched

by the hand considerable irritation is set up.

=Fertility of Spiders.=—Spiders vary greatly in the average number of

eggs laid by different species, and within the limits of each species

there is a very considerable variation in fertility. As a rule it

appears that the large and vigorous spiders are more prolific than the

smaller and weaker members of the order. Were all the facts before us,

however, we should no doubt find that the number of eggs laid bore a

direct proportion, not to the size of the species, but to the dangers to

which the young of that species are exposed. Where the total numerical

strength of a species is fairly stationary, such a proportion must of

course exist. Some species, no doubt, are tending to become extinct,

while others are increasing in numerical importance. As a general rule,

however, it is safe to infer that, if a species is especially prolific,

special dangers attend the rearing of the young. The largest of North

American Epeirids, _Argiope cophinaria_,[287] constructs a cocoon

containing, on an average, 1150 eggs. As many as 2200 have been counted

in exceptional cases. Even this number is exceeded in the case of some

of the great Aviculariidae. _Theraphosa leblondi_ deposits as many as

3000 eggs. The large European Epeirids, _E. quadrata_ and _E.

diademata_, lay about 600 eggs, those of _Lycosa narbonensis_ reaching

about the same number. Those American spiders which have been described

as stringing up a series of cocoons in their webs usually attain about

the same aggregate, the eggs being less numerous in each cocoon.

These are examples of fairly large and fertile spiders. In the case of

other species the number of eggs laid is exceedingly small. _Ero

furcata_ makes a single cocoon containing six eggs. _Synageles picata_,

an ant-like Attid, lays only three. _Oonops pulcher_ constructs several

cocoons, but each contains only two eggs. The eggs of Cave-spiders, and

such as live in dark and damp places, are generally few in number.

_Anthrobia mammouthia_, for example, an inhabitant of the great American

caves, deposits only from two to five eggs.

Our knowledge of the special perils which beset particular species is so

incomplete that we are often at a loss for the reason of this great

inequality in fertility. For instance, how does _Synageles picata_

maintain its numerical strength by laying only three eggs, when, as

M‘Cook points out, its resemblance to the ant, though advantageous to

the adult spider, affords no protection to the egg? Our knowledge must

be greatly extended before we are able to account for particular cases.

Many influences hostile to spiders as a group are, however, well known,

and we may here enumerate them.

=Natural Enemies.=—The precautions taken by the mother in constructing

the cocoon render the inclemency of the weather very much less

destructive to the eggs than to the newly-hatched young. Nevertheless,

among spiders inhabiting swampy regions great havoc is wrought by the

occasional wholesale swamping of the cocoons by floods. Professor Wilder

considers the great fertility of _Nephila plumipes_ necessary to

counterbalance the immense destruction worked by the heavy rains upon

their cocoons, which are washed in great numbers from the trees, to the

leaves of which they are attached. But such exposed situations are

avoided by many species, and their eggs, enclosed in their silken

envelope, are well protected against the severities of the weather.

A more universal enemy to the egg is found in Ichneumon flies. On

examining the cocoons of almost any species of spider, a large

proportion are almost certain to be found to contain Ichneumon larvae.

Mr. F. Smith, in the _Transactions of the Entomological Society_ for

1860, describes two species, _Hemeteles fasciatus_ and _H. formosus_,

which are parasitic on the eggs of _Agelena brunnea_. They are figured

in Mr. Blackwall’s book on British Spiders. _Pezomachus gracilis_

attacks the cocoons of many kinds of American spiders, appearing to have

no special preference for any particular species, while _Acoloides

saitidis_ seems to pay special attention to the eggs of certain of the

Jumping-spiders, and particularly of _Saitis pulex_.

The Ichneumons which thus regard the Spider’s eggs as convenient food

for their own larvae are probably very numerous. Nor are they themselves

always free from parasites. Occasionally the larvae of minute

Hymenopterous insects are found to be parasitic upon the eggs of an

Ichneumon which have been laid in a Spider’s cocoon.

It sometimes happens that the development of the young spiders has so

far advanced at the time of the Ichneumon’s intrusion that the latter’s

intention is frustrated, and its offspring, instead of devouring, are

themselves devoured. Again, some few of the eggs in an infested cocoon

occasionally escape the general destruction and reach the adult

condition, but there can be no doubt that Ichneumons are largely

instrumental in keeping down the numbers of most species of spiders. The

perils which attend the Spider after leaving the cocoon are no less

formidable, and much more numerous. The whole newly-hatched brood may be

destroyed by a heavy rain-storm. If there is not a sufficient supply of

food suitable to their feeble digestive powers they perish of inanition,

or eat one another. This cannibalistic propensity is a considerable

factor in the mortality among young spiders, and the adult animals

frequently prey upon one another.

_Argyrodes piraticum_, in California, invades the webs of larger spiders

of the family Epeiridae, which it seizes and devours. _A. trigonum_,

common in the eastern states of North America, has the same habit.[288]

Hentz found in Alabama a spider, which he named _Mimetus interfector_,

of still more ferocious and piratical habits. Its special quarry is

_Theridion tepidariorum_. Sometimes the _Theridion_ overcomes the

invader, and one case was observed in which a second _Mimetus_ was

devouring a _Theridion_ beside the dead body of its predecessor, who had

come off the worse in the combat.

The eggs of _Theridion tepidariorum_ are also sometimes devoured by this

spider, and a similar propensity has been observed in some English

species, for Staveley[289] states that it is common to see certain

spiders of the genus _Clubiona_ feeding upon the eggs which have been

laid by their neighbours. The larvae of some Hymenopterous insects are

parasitic upon Spiders themselves, and not upon their eggs. Blackwall

found this to be the case with the larvae of _Polysphincta carbonaria_,

an Ichneumon which selects spiders of the genera _Epeira_ and _Linyphia_

on which to deposit its eggs.[290] The spider thus infested does not

moult, and is soon destroyed by the parasite which it is unable to

dislodge from its back. Menge, in his _Preussische Spinnen_, enumerates

several cases of parasitism in which the larva, as soon as it has

developed from the egg, enters the spider’s body, there to continue its

growth. Spiders are also subject to the attack of a parasitic worm,

_Gordius_ (cf. vol. ii. p. 173).

Some of the most deadly foes of Spiders are the Solitary Wasps. There

are many species of _Pompilus_ (vol. vi. p. 101), which, having

excavated holes in clay banks, store them with spiders or other

creatures which they have paralysed by their sting. They then deposit an

egg in the hole, and immediately seal up the orifice. This habit is

found to characterise the solitary wasps of all parts of the world.

Belt[291] relates the capture of a large Australian spider by a wasp.

While dragging its victim along, it was much annoyed by the persistent

presence of two minute flies, which it repeatedly left its prey to

attempt to drive away. When the burrow was reached and the spider

dragged into it, the two flies took up a position on either side of the

entrance, doubtless with the intention of descending and laying their

own eggs as soon as the wasp went away in search of a new victim.

Fabre[292] gives an interesting account of one of the largest European

Pompilidae, _Calicurgus annulatus_, which he observed dragging a

“Tarentula” to a hole in a wall. Having with great difficulty introduced

its burden into the cavity, the wasp deposited an egg, sealed up the

orifice, and flew away. Fabre opened the cell and removed the spider,

which, though completely paralysed, lived for seven weeks.

The same indefatigable observer describes the method adopted by the

comparatively small _Pompilus apicalis_ in attacking the formidable

Wall-spider, _Segestria perfida_. The combatants are well matched, and

the issue of the battle would be doubtful if the wasp did not have

recourse to stratagem. Its whole energies are directed towards forcing

the spider away from its web. At home, it is confident and dangerous;

when once dislodged, it appears bewildered and demoralised. The wasp

darts suddenly towards the spider and seizes it by a leg, with a rapid

effort to jerk it forth, releasing its hold before the enemy has had

time to retaliate. The spider, however, as well as being anchored by a

thread from its spinnerets, is clinging to its web with its hind legs,

and if the jerk is not sufficiently energetic, it hastily scrambles back

and resumes its defensive position. Before renewing the attack the wasp

gives the spider time to recover from the excitement of the first onset,

seeking, meanwhile, the retreats of other victims. Returning, it

succeeds, by a more skilful effort, in drawing the spider from its

retreat and hurling it to the ground, where, terrified and helpless, it

falls an easy prey. Should the insect bungle in its first attack and

become entangled in the web, it would itself become the victim. Certain

wasps thus appear to seek out particular species of spiders as food for

their larvae. Others are less discriminate in their tastes. Again, some,

as in the cases cited above, store their egg-nest with a single spider,

while others collect many for the purpose.

The American “blue digger wasp” (_Chlorion caeruleum_) excavates its

nest in the ground, and inserts a single large spider of any

species.[293] Another wasp, of the genus _Elis_, selects the

Wolf-spiders, and especially _Lycosa tigrina_, for the use of its

larvae, while _Priocnemus pomilius_ shows a preference for the

Crab-spiders, or Thomisidae.

One of the most remarkable instances is that of _Pepsis formosa_, which

preys upon the gigantic spider _Eurypelma hentzii_, wrongly styled in

America the “tarantula,” but really belonging to an entirely different

family, the Aviculariidae.

Fabre’s most interesting researches have established the fact that the

instinct of the wasp leads it to sting the spider in a particular spot,

so as to pierce the nerve-ganglion in the thorax. The precision with

which this is effected is absolutely necessary for the purpose of the

insect. If stung elsewhere, the spider is either incompletely paralysed,

or it is killed outright, and thus rendered useless as food for the

future larvae of the wasp. On the one hand, therefore, the Tarantula has

acquired the habit of striking the wasp in the only point where its blow

is instantaneously fatal, while on the other the wasp, with a different

object in view, has been led to select the precise spot where its sting

will disable without immediately destroying the spider. The latter case

is, if anything, the more extraordinary, as the insect can hardly have

any recollection of its larval tastes, and yet it stores up for progeny,

which it will never see, food which is entirely abhorrent to itself in

its imago state.

Spiders taken from the egg-nests of wasps by M‘Cook survived, on the

average, about a fortnight, during which period they remained entirely

motionless, and would retain any attitude in which they were placed.

There are many animals which either habitually or occasionally feed upon

spiders. They are the staple food of some hummingbirds, and many other

birds appear to find in them a pleasing variation on their customary

insect diet. These creatures, moreover, are destructive to spiders in

another way, by stealing the material of their webs, and especially the

more closely textured silk of their egg-cocoons, to aid in the

construction of their nests. M‘Cook has observed this habit in the case

of _Vireo noveborocensis_, and he states, on the authority of others,

that the “Plover” and the “Wren” are addicted to it. The smaller species

of monkeys are extremely fond of spiders, and devour large numbers of

them. They are said, moreover, to take a mischievous delight in pulling

them in pieces. Armadillos, ant-eaters, snakes, lizards, and indeed all

animals of insectivorous habit, draw no distinction between Insecta and

Arachnida, but feed upon both indiscriminately. The army ants, so

destructive to insect life in tropical countries, include spiders among

their victims. These formidable insects march along in vast hordes,

swarming over and tearing in pieces any small animal which lies in their

path. They climb over intervening obstacles, searching every cranny, and

stripping them bare of animal life. Insects which attempt to save

themselves by flight are preyed upon by the birds, which are always to

be seen hovering above the advancing army. The spider’s only resource is

to hang from its thread in mid-air beneath the branch over which the

ants are swarming, for the spider line is impracticable to the ant.

Belt[294] has observed a spider escape the general destruction by this

means.

=Protective Coloration.=—Examples are numerous in which the spider

relies upon the inconspicuousness not of its nest, but of itself, to

escape its natural foes. Its general hues and markings are either such

as to render it not readily distinguishable among its ordinary

surroundings, or the principle has been carried still further, and a

special object has been “mimicked” with more or less fidelity.

This country is not rich in the more striking mimetic forms, but the

observer cannot fail to notice a very general correspondence in hue

between the spiders of various habits of life and their environment.

Those which run on the ground are usually dull-coloured; tree-living

species affect grey and green tints, and those which hunt their food

amongst sand and stones are frequently so mottled with yellow, red, and

grey, that they can scarcely be recognised except when in motion.

A few of our indigenous species may be mentioned as especially protected

by their colour and conformation. _Tibellus oblongus_ is a

straw-coloured spider with an elongated body, which lives among dry

grass and rushes. When alarmed it clings closely to a dry stem, remains

motionless, and escapes observation by its peculiarity of colour and

shape. _Misumena vatia_, another of the Thomisidae or Crab-spiders,

approximates in colour to the flowers in which it is accustomed to lurk

on the watch for prey. It is of a variable hue, generally yellow or

pink, and some observers believe that they have seen it gently waving

its anterior legs in a way which made them easily mistaken for the

stamens of the flower stirred by the breeze. Its purpose appears to be

to deceive, not its enemies, but its victims. It seems to be partial to

the blooms of the great mullein (_Verbascum thapsus_), and

Pickard-Cambridge has more than once seen it seize and overcome a bee

which had visited the flower in search of honey. He has also observed it

in the blossoms of rose and furze bushes.[295]

An Epeirid (_Tetragnatha extensa_) resembles _Tibellus_ in its method of

concealing itself when alarmed. It also possesses an elongated abdomen,

of a grey-green tint, which it closely applies to one of the twigs among

which it has stretched its net, at the same time extending its four long

anterior legs straight before it, and in this position it lies _perdu_,

and is very easily overlooked. Another Orb-weaver, _Epeira cucurbitina_,

is of an apple-green colour, which is admirably calculated to conceal it

among the leaves which surround its snare.

Most of our English Attidae, or Jumping-spiders, imitate closely the

prevailing tone of the surfaces on which they are accustomed to hunt.

This will be recognised in the familiar striped Wall-spider, _Salticus

scenicus_, and we may also mention the grey _Attus pubescens_, which

affects stone walls, and the speckled _Attus saltator_, which is hardly

distinguishable from the sand which it searches for food.

Examples may also be found among the Lycosidae or Wolf-spiders. Of the

prettily variegated _Lycosa picta_, Pickard-Cambridge says: “Much

variation exists in the extent of the different portions of the pattern

and in their depth of colouring, these often taking their prevailing

tint from the colour of the soil in which the spider is found. The best

marked, richest coloured, and largest examples are found on sandy and

gravelly heaths, where there is considerable depth and variety of

colouring.... But on the uniformly tinted greyish-yellow sandhills

between Poole and Christchurch I have found a dwarf, pale yellow-brown

variety, with scarcely any dark markings on it at all, the legs being of

a uniform hue, and wholly destitute of dark annuli.”[296]

=Mimicry.=—In the island of Portland, a locality remarkable for the

number of species peculiar to itself, there is found a spider, _Micaria

scintillans_, very closely resembling a large blackish ant which

frequents the same neighbourhood. Its movements, moreover, are

exceedingly ant-like, as it hurries along in a zigzag course, frequently

running up and down grass stems after the manner of those insects. It is

a great lover of sunshine, and disappears as soon as the sun is obscured

by a passing cloud.

Such resemblances, obvious enough in nature, and heightened by the

behaviour of the mimetic form, are often by no means striking in the

cabinet. In some American species of spiders, however, imitation of the

ant has passed beyond the stage of a general resemblance as regards size

and colour and method of progression. The head of the ant is well marked

off from the body, and the thorax is frequently divided into distinct

regions. These peculiarities are imitated by constrictions in the

cephalothorax of mimetic spiders. The resemblance, moreover, is much

increased by their habit of using but six legs for locomotion, and

carrying the second pair as ants do their antennae. The best known

examples of these spiders are _Synageles picata_ and _Synemosyna

formica_ (see Fig. 215, C, p. 420), and even more striking resemblances

have been observed among some undescribed South American species.

The object of such mimicry seems to vary in different cases. Sometimes

the spider preys upon the ant which it resembles. Sometimes, again, by

its disguise, it escapes the notice of the ant which would otherwise

feed upon it. More often spider and ant are neutral as regards each

other, but, under cover of its resemblance, the Arachnid is enabled to

approach an unsuspecting victim to which the ant is not a terror. Again,

the unpleasantly acid taste of ants is unpalatable to most birds, though

not to all, and the increased danger from specially ant-eating birds may

be more than counterbalanced by the immunity they acquire from other

birds.

There is quite a large class of Spiders of nocturnal habits, whose only

precaution by day is to sit perfectly still and be mistaken for

something else. We have referred to the adaptation in colour of our

English species, _Misumena vatia_, to the flowers in which it lies in

wait for prey. Bates[297] mentions exotic examples of the same family

which mimic flower-buds in the axils of leaves. Herbert Smith says of a

spider which sits upon a leaf waiting for prey: “The pink three-lobed

body appears just like a withered flower that might have fallen from the

tree above; to the flies, no doubt, the deception is increased by the

strong sweet odour, like jasmine.”

Trimen[298] describes a Cape Town species which is of the exact rose-red

of the flower of the oleander. “To more effectually conceal it, the

palpi, top of the cephalothorax, and four lateral stripes on the abdomen

are white, according remarkably with the irregular white markings so

frequent on the petals of _Nerium_.”

The same observer, approaching a bush of the yellow-flowered _Senecio

pubigera_, noticed that two of the numerous butterflies settled upon it

did not fly away with their companions. Each of these he found to be in

the clutches of a spider, whose remarkable resemblance to the flower lay

not only in its colour, but in the attitude it assumed. “Holding on to

the flower-stalk by the two hinder pairs of legs, it extended the two

long front pairs upward and laterally. In this position it was scarcely

possible to believe that it was not a flower seen in profile, the

rounded abdomen representing the central mass of florets, and the

extended legs the ray florets; while, to complete the illusion, the

femora of the front pair of legs, adpressed to the thorax, have each a

longitudinal red stripe which represents the ferruginous stripe on the

sepals of the flower.”

Cambridge found in Palestine some species of Thomisidae which, when at

rest, were indistinguishable from bits of coarse fleecy wool, or the

rough seeds of some plant.

There is perhaps no more curious case of mimicry than that of a spider,

_Phrynarachne_ (= _Ornithoscatoides_) _decipiens_, which Forbes

discovered in Java while butterfly-hunting. It appears that butterflies

of the Family Hesperidae have a custom of settling, for reasons best

known to themselves, upon the excreta of birds, dropped upon a leaf.

Forbes noticed one in this position. Creeping up, he seized the

butterfly, but found it mysteriously glued by the feet. On further

investigation the “excreta” proved to be a spider. So accurate was the

mimicry that he was again completely deceived by the same species in

Sumatra. Its habit is to weave upon a leaf a small white patch of web,

of a shape which greatly assists the deception, and in the midst of this

it lies on its back, holding on by the spines with which its legs are

furnished. It then folds its legs over its thorax, and waits for some

insect to settle upon it.

In rare cases spiders have come to resemble their enemies the Ichneumon

flies. A frequent habit of these insects is to deposit their eggs in the

newly-formed cocoon of the spider. The Ichneumon eggs are the first to

hatch, and the larvae have a convenient food-supply at hand. Sometimes,

however, they adopt another method, and insert their eggs into the body

of the spider itself. It is probably in order to avoid this unpleasant

contingency that the spider has evinced towards the Ichneumon the

sincerest form of flattery.

=The Senses of Spiders.=

SIGHT.—Though, as has been shown, spiders are well provided with eyes,

their power of vision, in most cases, is by no means remarkable. As

might be expected, it is less developed in those of sedentary than in

those of nomadic habit.

It is noticeable that, in most spiders, some of the eyes are of a pearly

grey colour, and others of a much darker hue. Simon designates the

former _nocturnal_ and the latter _diurnal_ eyes, according to the

special use which he believes them to subserve.

This view of the matter cannot be regarded as at all established, and

has not found general acceptation. Moreover, Pillai[299] has shown that

certain Attid spiders can change the colour of their eyes by a movement

of the internal mechanism. The Epeiridae, spinners of the round web, are

certainly, as a rule, very dim-sighted creatures. A fly may be held

within an inch of them, but, unless it buzz, it will excite no notice

whatever. A careful observation of the performances of the large

Garden-spider in securing her prey will soon convince the onlooker that

she is guided almost entirely by appeals to her sense of touch

communicated along the tremulous lines of her snare. Interpreting these

too hastily, she will sometimes rush straight past the entangled fly,

and wait for it to renew its struggles before making sure of its

whereabouts. Keen sight would be of little utility to such spiders, as

they are concerned with nothing beyond the limits of their snare, and

within its range they are furnished with the equivalent of complete

telegraphic communication.

That most of the vagabond spiders can see well within the range of

several inches there is no doubt, though some observers have been misled

by the result of certain experiments on the Lycosidae, or

“Wolf-spiders.” It will be remembered that the female Lycosid carries

her egg-bag about with her, attached usually to her spinnerets. If it be

removed and placed close at hand, the spider experiences the greatest

difficulty in finding it again. Lubbock attributed this to defective

sight, whereas it merely arises from unfamiliarity with the _appearance_

of the egg-bag, which, since its construction, has been so situated as

to be out of the view of the spider. Peckham found that spiders of the

genus _Theridion_, accustomed to the sight of their cocoons, readily

recognised them by that sense when removed to a distance.

The most keen-sighted of the spider tribe are undoubtedly the Attidae,

or Leaping-spiders. The little black and white striped Wall-spider,

_Salticus scenicus_, is probably a familiar object to most of our

readers, and a very little observation of its movements, like those of a

cat stalking a bird, will convince the observer that its visual powers

are wonderfully keen and accurate. Its attitude of “attention” on

sighting its prey, its stealthy manœuvring to approach it unobserved,

and the unerring certainty of its final leap, are very interesting to

witness.

It is somewhat noticeable that both in the Epeiridae and in the Attidae

the two portions of the body, cephalothorax and abdomen, have more than

the usual freedom of independent motion. In the Orb-weavers this gives

play to the spinnerets in binding up a captured insect, but in the

Leaping-spiders it allows of the rapid directing of the large anterior

eyes towards the quarry, as it continually alters its position.

Professor and Mrs. Peckham of Wisconsin[300] performed some interesting

experiments to ascertain the sensitiveness of the spider’s eye to

colour. Freely communicating compartments of differently coloured glass

were constructed, and spiders were confined in them, when it was found

that red was the most and blue the least attractive hue. This agrees

well with what Lubbock found to be the case with ants, but those insects

displayed a greater antipathy for blue and not so marked a preference

for red.

HEARING.—Most of our knowledge about the auditory sense of spiders is

due to experiments performed by C. V. Boys,[301] and repeated by

Professor and Mrs. Peckham.

The spider usually responds to the stimulus in one of two ways; it

either raises its front legs, extending them in the direction of the

sound, or it allows itself to drop suddenly, as though in alarm. It was

only in the case of the Epeiridae that any results were obtained, and

these spiders were more sensitive to low than to high notes. Now, as

M‘Cook points out, it is exceedingly strange that the nomadic and

hunting spiders, to which the sense of hearing might be expected to be

extremely useful, should be deficient in this faculty, while the

sedentary spiders, to which it would appear comparatively unimportant,

should possess it in a tolerably developed form. That writer may

possibly be correct in supposing that the sense, as possessed by

spiders, is hardly differentiated from that of ordinary touch, and that

the web-making species are only aware of sounds by the vibrations

communicated to their feet by the medium of the web. However this may

be, we must reluctantly but sternly reject the numerous and seemingly

authentic stories, often connected with historic personages, which

credit the spider with a cultivated taste for music.

We have seen that among the spiders which possess a stridulating

apparatus it is confined, in certain groups, to the male, or if present

in the female it exists only in a rudimentary form. If in these cases

stridulation has been rightly interpreted as a sexual call, the power of

hearing, at least in the female, is of course connoted. The spiders in

question are members of the Theridiidae, a family closely allied to the

Epeiridae, and therefore more likely than most groups to possess the

power of hearing.

Theraphosid spiders show no response to the stimulus of sound, and among

them stridulation is not confined to one sex. If, as is generally

believed, the organ is used to warn off enemies, it is not necessary

that the sound produced should be audible to the spider itself. If there

be any true hearing organ in spiders its location is quite uncertain.

Some have supposed the so-called lyriform organs in the legs to have an

auditory function, while others have supposed the power of hearing to

reside in certain hairs, of which there are several different types

distributed over the body and limbs of the animal.

=Spider Intelligence.=—The experiments performed by the Peckhams clearly

proved that spiders have short memories—a sure indication of a low state

of intelligence. Members of the Lycosid or “Wolf-spider” group, when

deprived of their cocoons, recognised them again after a few hours, but

in most instances they refused to resume them after a lapse of

twenty-four hours, and in every case an absence of two days sufficed to

prevent any sign of recognition on their restoration. Moreover, when,

after a shorter interval, the cocoons of other spiders, even of

different genera, were offered to them, they appeared equally satisfied,

and attached them in the orthodox manner, beneath the abdomen. The same

treatment was even accorded to pith balls, which, if of the right size,

seemed to be a perfectly satisfactory substitute. The contents of one

cocoon were replaced by a shot three or four times their weight, but the

spider accepted it with alacrity, spending half an hour in refixing it,

when its weight caused it to fall from its attachment.

The habit of “feigning death,” which seems to be especially

characteristic of the Epeiridae or orb-weaving spiders, probably arises

from no desire to deceive its adversary as to its _condition_, but from

an instinct to remain motionless, and therefore inconspicuous. Where a

nomadic spider seeks safety in flight, a sedentary species finds a

greater chance of escape in dropping a certain distance, and, while

still attached by its silken line, giving as little evidence of its

whereabouts as possible—trusting, in many cases, to its protective

colouring. This method, moreover, has the advantage of facilitating its

return to the web when the danger is past—a feat of which it would be

quite incapable were it once to relinquish its clue.

All the remarkable and apparently intelligent actions of these creatures

seem to be done in obedience to a blind instinct, which is obeyed even

when there is no longer any object to be served. We have seen how the

Trap-door spiders decorate the lids of their nests with moss even when

the surrounding ground is bare, and _Agelena labyrinthica_ has been

observed to go through the whole lengthy and laborious operation of

constructing its egg-cocoon though all its eggs were removed immediately

on being laid.[302]

=Mating Habits.=—The sex of a mature spider can readily be recognised by

the palpus which, as we have seen, is furnished in the male with a

“palpal organ.” After the last moult but one the palp appears tumid, but

it is only at the last moult that the organ is fully formed, and that

the genital orifice is visible under the anterior part of the abdomen.

No alteration takes place in the female palp at maturity, but it is only

after the last moult that the “epigyne” is distinguishable.

[Illustration:

FIG. 198.—_Argiope aurelia_, ♂ and ♀, natural size.

]

That the palpal organs are used in the fertilisation of the female has

long been established. How they came to contain the sperm matured in the

abdomen was a problem which has only been solved comparatively recently.

No direct connection could be found by way of the palpus with the

abdominal organs, which, indeed, were seen to have an orifice between

the lung-sacs. It is now known that some spiders at all events spin a

slight web upon which they deposit a drop of spermatic fluid, which they

afterwards absorb into their palpal organs for transference to the

female. Secondary sexual differences are often very marked, the male

being almost invariably the smaller in body, though its legs are

frequently longer and more powerful than those of the female.

Among some of the sedentary spiders the disparity in size is excessive.

The most striking examples are furnished by the Epeirid genera _Argiope_

and _Nephila_, the male in some instances not attaining more than the

thousandth part of the mass of the female. The coloration of the sexes

is frequently quite dissimilar, the male being usually the darker,

though in the Attidae he is in many cases the more strikingly

ornamented.

In the minute Theridiid spiders of the group Erigoninae (see p. 404),

the male cephalothorax often presents remarkable and characteristic

excrescences not observable in the female. Some curious examples of this

phenomenon may be seen in Fig. 209.

To the ordinary observer male spiders will appear to be comparatively

rare, and to be greatly outnumbered by the females. This is probably to

some degree true, but the unsettled habits of the males and the shorter

duration of their life are calculated to give an exaggerated impression

of their rarity. They only appear in considerable numbers at the mating

season, shortly after which the males, in the case of many species, may

be sought for in vain, as, after performing their functions, they

quickly die. The snares they spin are often rudimentary, their

capabilities in this direction appearing to deteriorate after the adult

form is attained. Young spiders of indistinguishable sex make perfect

snares on a small scale, while such as eventually develop male organs

will often thereafter be content with a few straggling lines made with

very slight regard to symmetry. They become nomadic in their habits,

wandering off in search of the females, and pitching a hasty tent by the

way.

The relations between the sexes in the Spider tribe present points of

extreme interest, but in this connexion the various groups must be

separately treated on account of their very different habits of life.

In no group are these relations more curious than in the Epeiridae, the

constructors of the familiar wheel-like web. Love-making is no trifling

matter here. If the female is not in the mood for the advances of the

male she will probably regard him as a desirable addition to her larder.

Even if his wooing is accepted, he has to beat a precipitate retreat

after effecting his purpose, or he may fall a victim to his partner’s

hunger.

This strange peril braved by the male in courting the female, which has,

as far as is known, no parallel in any other department of the animal

kingdom, is frequently mentioned as universal among spiders. It

unquestionably exists, and may be verified by any patient observer in

the case of the large Garden-spider _Epeira diademata_, but it has only

been observed among certain species of the Epeiridae and Attidae. It

will be remembered that in the Epeiridae the males are sometimes

absurdly small in comparison with the females, and this diminution of

size is thought to have a direct connection with the danger undergone at

the mating season. Small active males stand a better chance of escape

from ferocious females, so that natural selection has acted in the

direction of reducing their size as far as is compatible with the

performance of their functions.

Pickard-Cambridge[303] cites an extreme case. He says: “The female of

_Nephila chrysogaster_, Walck. (an almost universally distributed

tropical Epeirid), measures 2 inches in the length of its body, while

that of the male scarcely exceeds ⅒th of an inch, and is less than

¹⁄₁₃₀₀th part of her weight.”

During the mating season the males may be looked for on the borders of

the snares of the females. Their action is hesitating and irresolute, as

it well may be, and for hours they will linger on the confines of the

web, feeling it cautiously with their legs, and apparently trying to

ascertain the nature of the welcome likely to be extended to them. If

accepted, they accomplish their purpose by applying their palps

alternately to the epigyne of their mate. If repulsed, they do their

best to make their escape, and wait for a more auspicious moment.

Emerton[304] says: “In these encounters the males are often injured;

they frequently lose some of their legs; and I have seen one, that had

only four out of his eight left, still standing up to his work.”

Among the other groups of sedentary spiders the relations between the

sexes seem to be more pacific, and there is even some approach to

domesticity. Males and females of _Linyphia_ may be found during the

mating season living happily together in their irregular snares. The

same harmony seems to exist among the Tube-weavers, and _Agelena

labyrinthica_ lingers for days unmolested about the web of the female,

though it is perhaps hardly correct to say that they have their home in

common.

Among the wandering spiders the male usually seeks out the female and

leaps on her back, from which position his sperm-laden palps can reach

their destination. This is the habit of the Thomisidae or Crab-spiders,

and of the quick-running Wolf-spiders, or Lycosidae.

[Illustration:

FIG. 199.—Male _Astia vittata_ dancing before the female. (After

Peckham.)

]

The sexual relations of the Leaping-spiders, or Attidae, are so

remarkable as to deserve a longer notice. This Family includes the most

beautiful and highly ornamented examples of spider life. Their

headquarters are the tropics, and their brilliant colouring led Wallace

to speak of those he saw in the Malay Archipelago as “perfect gems of

beauty.”

Now among these spiders the male is almost always more highly decorated

than the female, and Peckham’s observations would lead to the conclusion

that the female is influenced by the display of these decorations in the

selection of her mate.

The so-called “love-dances” of certain tropical birds are known to all

readers of natural history, but it was hardly to be expected that their

counterpart would exist among spiders. Yet the antics by which male

Attidae endeavour to attract the attention of the females afford an

almost exact parallel.

The following extract from the account of Professor and Mrs.

Peckham[305] of their observations on _Saitis pulex_ will make this

abundantly clear: “When some four inches from her he stood still, and

then began the most remarkable performances that an amorous male could

offer to an admiring female. She eyed him eagerly, changing her position

from time to time, so that he might be always in view. He, raising his

whole body on one side by straightening out the legs, and lowering it on

the other by folding the first two pairs of legs up and under, leaned so

far over as to be in danger of losing his balance, which he only

maintained by sidling rapidly towards the lowered side.... Again and

again he circles from side to side, she gazing towards him in a softer

mood, evidently admiring the grace of his antics. This is repeated until

we have counted a hundred and eleven circles made by the ardent little

male. Now he approaches nearer and nearer, and when almost within reach

whirls madly around and around her, she joining with him in a giddy

maze. Again he falls back and resumes his semicircular motions, with his

body tilted over; she, all excitement, lowers her head and raises her

body so that it is almost vertical; both draw nearer; she moves slowly

under him, he crawling over her head, and the mating is accomplished.”

[Illustration:

FIG. 200.—Dancing attitude of male _Icius mitratus_. (After Peckham.)

]

A similar but not exactly identical performance was gone through by the

male of several different species, but it was noteworthy that the

particular attitudes he adopted were always such as to display to the

best advantage his special beauties, whether they consisted in crested

head, fringed palpi and fore-legs, or iridescent abdomen. Sometimes even

such exertions failed to captivate the female, and she would savagely

attack the male, occasionally with fatal effect.

In the case of some species, when the male had won the consent of his

mate, he would weave a small nuptial tent or web, into which he would

partly lead and partly drive the female, who no longer offered serious

resistance.

=Fossil Spiders.=

About 250 species of fossil spiders have been discovered. Of these about

180 are embedded in amber, a fossil resinous substance which exuded from

ancient coniferous trees, and quantities of which are annually washed up

from the Baltic upon the shores of northern Prussia.

The most ancient fossil spider known was obtained from the argillaceous

slate of Kattowitz in Silesia, and belongs, therefore, to the

Carboniferous strata of the Palaeozoic epoch. It has been named

_Protolycosa anthrocophila_. There is some doubt as to the affinities of

this spider. Roemer, who described it, placed it among the Citigradae,

while others have thought it to belong rather to the Territelariae.

Thorell, on account of its agreement in certain important points with

the very curious recent Malay spider _Liphistius_, has placed them both

in a separate sub-family, Liphistioidae. To the same epoch belongs the

American fossil spider _Arthrolycosa antiqua_, which was found in the

Coal measures of Illinois.

The other localities from which fossil spiders have been obtained are

the Swiss Miocene at Oeningen, the Oligocene deposits at Aix, the

Oligocene of Florissant, Colorado, Green River, Wyoming, and Quesnel,

British Columbia.

Many of the spiders from the rocks are so fragmentary that it is

impossible to decide with certainty on their systematic position, but a

considerable number of them—more than half—have been assigned to recent

genera.

The amber spiders are mostly well preserved, and can be classified with

more certainty. Many of them are surprisingly like existing forms,

though others, like _Archaea paradoxa_, differ greatly from most spiders

now extant, though they show some affinities with one or two remarkable

and aberrant forms.