The Cambridge Manuals of Science and
Literature
SPIDERS
CAMBRIDGE UNIVERSITY PRESS
London: FETTER LANE, E.C.
C. F. CLAY, MANAGER
[Illustration]
Edinburgh: 100, PRINCES STREET
London: WILLIAM WESLEY & SON, 28, ESSEX STREET, STRAND
Berlin: A. ASHER AND CO.
Leipzig: F. A. BROCKHAUS
New York: G. P. PUTNAM’S SONS
Bombay and Calcutta: MACMILLAN AND CO., LTD.
_All rights reserved_
[Illustration: The Banana Spider, natural size, from a photograph by Mr
James Adams.]
SPIDERS
BY
CECIL WARBURTON, M.A.
Christ’s College
Zoologist to the Royal Agricultural
Society
Cambridge:
at the University Press
1912
[Illustration]
Cambridge:
PRINTED BY JOHN CLAY, M.A.
AT THE UNIVERSITY PRESS
_With the exception of the coat of arms at the foot, the design on
the title page is a reproduction of one used by the earliest known
Cambridge printer, John Siberch, 1521_
PREFACE
The modest dimensions of this book are perhaps sufficient indication
that it is not intended as an aid to the collector. There are about
five hundred and fifty known species of spiders in the United Kingdom
alone, and at least an equal number of pages would be needed to
describe them.
Our concern is with the habits and modes of life of spiders—especially
of such as are most frequently met with and most easily recognised, and
the reader, especially if he is fortunate enough to spend an occasional
holiday in southern Europe, will find little in the following pages
which he cannot verify—or disprove—by his own observations. Indeed
the hope that some of his readers may be induced to investigate on
their own account has actuated the writer throughout, and has led
him to lay considerable stress upon the methods of research and the
ingeniously devised experiments by means of which whatever knowledge we
possess has been obtained.
CECIL WARBURTON
CAMBRIDGE
_March, 1912_
CONTENTS
CHAP. PAGE
I. A Survey of the Field. Evidences of spider industry.
Where to look for spiders. Variety of habits 1
II. What is a Spider? The Arthropoda and their
divisions. Arachnida. Characteristics of a
spider. Spinnerets and their use 5
III. The Circular Snare. Foundation lines. The
spiral with its viscid beads. The building of
the snare. Why the spider is not caught in
its own snare 13
IV. The Mental Powers of Spiders. The human standpoint.
Instinct. Sight. Hearing. Smell.
Taste. Memory and “educability” 20
V. Trap-snares and Balloons. Variations of the
circular snare. The snare of _Hyptiotes_.
Webs of _Theridion_ and _Linyphia_. The iron
railing and its aeronauts. A race congress.
Gossamer. Geographical distribution 30
VI. _Agelena._ Its web. The spider and its behaviour
in captivity. The platform and its carpet.
The construction of the cocoon. Instinctive,
not intelligent 38
VII. Water-Spiders. Marine spiders. The fresh-water
spider. The diving bell, and how it
is filled with air. Behaviour of the male.
Winter and summer houses 47
VIII. Crab-Spiders.—Mimicry. The appearance of
crab-spiders. Their haunts. Protective
coloration and resemblance. Habits correlated
with structure. Probable origin of
“mimicry” 52
IX. Wolf-Spiders. General habits. Semi-aquatic
species. Nomads and settlers. Structure.
Eyes. _Lycosa picta._ A colony in full swing.
The burrow. Egg-bags. Recognition of
cocoons. Want of discrimination. The
Tarantula. Its haunts and habits. The
death-stroke. The burrow and its parapet.
Sunning the cocoon. Carrying the young.
Poisonous properties 58
X. Jumping Spiders. The Zebra Spider. Its structure.
Its wonderful eyes. Hunting its prey.
The use of the drag-line. Sight in jumping
spiders. Love dances. Sham-fights. A
remarkable piece of research 76
XI. Theraphosid Spiders. Sub-division of the Order.
Mandibles. _Atypus_ and its nest. Its habits.
Aviculariidae. A giant spider. Trap-door
nests. Method of burrowing. “Bird-eaters,”
and their habits. _Dugesiella._ Poor sight but
remarkable sense of touch. _Psalmopoeus_
in captivity 87
XII. Stridulation. How sound is produced in Arthropoda.
Its purposes. Popular mistakes.
Spines and Keys. The purring spider 105
XIII. The Spinning Apparatus. Spinnerets. Their
mobility. Spools and spigots. Glands. Arrangement
in _Epeira_. No interweaving of lines. Functions
of glands. Spinning operations.
The Cribellum. The feet of spiders 110
XIV. The Enemies of Spiders. Cannibalism. Egg
parasites. Moulting. Starvation. Body
parasites. Solitary wasps. A gruesome fate 120
XV. Concluding Reflexions. The “use” of spiders.
Wide range of habits. Complexity of instincts.
The mystery of the egg. The storage of
energy. Economy in diet. Conclusion 126
LITERATURE 133
INDEX 135
LIST OF ILLUSTRATIONS
_Frontispiece._ The Banana Spider.
FIG.
1. A Spider, a Mite and a Harvestman 9
2. The Garden-spider and its snare 15
3. Stretching the viscid line 19
4. Preparing for flight 35
5. _Agelena_ at work 44
6. A Crab-spider 53
7. Wolf-spiders 64
8. A Jumping Spider 77
9. The eyes of a Jumping Spider 78
10. The love dance 84
11. Stridulating “keys” 108
12. Spinnerets 114
13. Spiders’ feet 119
CHAPTER I
A SURVEY OF THE FIELD
There are certain days of the year when the immense wealth of spider
industry going on all around us is revealed in a way calculated to
strike even the least observant. We all know—and derive no peculiarly
pleasant thrill from the knowledge—that we can, if so minded, find
abundance of cobwebs and their occupants by visiting the cellar or the
tool-house; and probably we have all at times noticed, with a languid
interest, large circular webs on our favourite rose-bushes, with a
spider motionless in the centre.
But some spring or autumn morning, when the night has been foggy and
the sun has only just succeeded in dispersing the mists, every bush and
hedge is seen to be draped, every square foot of lawn and meadow to be
carpeted with spiders’ silk. There has been no special activity in the
domain of these creatures, but every silken line is beaded with drops
perhaps fifty times its diameter, and what yesterday required careful
observation to detect is now visible yards away, and we realise for
once something of the prodigious activity constantly going on though
ordinarily unnoted.
And it never entirely ceases. True hibernation, if it ever occurs, is
not the rule among spiders, and there is no time of the year when some
species may not be found at work. Beat trees or bushes over an old
umbrella, or sweep grass and herbage with a sweeping net in summer,
and you will never draw a blank—some spiders are sure to be found. In
winter such measures are profitless, but if you take the trouble to
grub among ground vegetation, or shake fallen leaves over a newspaper,
or search under stones or logs of wood you will have no difficulty in
finding spiders enough, and by no means dormant. I have even seen an
enthusiastic collector remove inches of snow and disinter rare species
from among the roots of the grass beneath!
Spiders, then, are plentiful enough, and it is not only individuals
that are numerous but there are vastly more kinds or species than
most people dream of. The Rev. O. Pickard-Cambridge, in a book under
the modest title of _The Spiders of Dorset_ indispensable to all
British collectors, quaintly observes that most of his friends claim
acquaintance with three kinds of spiders—the garden spider, the
harvest spider and the little red spider—two of which, as it happens,
are not spiders at all. Yet the British List contains about five
hundred and fifty species, and the spiders of the world, though only
very partially investigated, already include many thousands of known
and described forms.
In this little work we shall not at all consider the spider tribe from
the collector’s point of view. We shall concern ourselves rather with
habits and modes of life and such structural modifications as are
correlated therewith. Certain well-defined groups of spiders we shall
recognise, but specific names will interest us little. And we might do
worse than step out on such a spring morning as we have imagined and
rapidly survey the field which lies open for our investigation.
First, then, examine a little more closely one of the garden bushes
in which the spiders have been so busy, and the chances are that
three different types of snare will be readily distinguishable. There
are sure to be some of the familiar wheel-like snares of _Epeira_,
but note also the fine-spun hammocks of _Linyphia_ with stay-lines
above and below, and the irregular labyrinths of _Theridion_, its
lines crossing and recrossing without apparent method. These are
sedentary spiders, and always to be found at home. All spiders spin
for some purpose or other, but these—or at all events _Epeira_—have
brought the art to its highest perfection. Leave them for the present
and examine a sunny wall or fence. You may chance to see a little
zebra-striped, flat-bodied spider exploring the surface and directing
its opera-glass-like eyes in all directions in search of prey. This is
one of the Attidae or jumping spiders—few and sober-coloured in this
country, but extraordinarily abundant and often extremely beautiful in
tropical regions. Pause at the iron railing before leaving the garden
and observe how the topmost bar and the knobs which crown the uprights
are alive with spiders, mostly very small, and obviously of many
different kinds, extremely busy about something that it may be worth
while to investigate later; then go on into the lane, and note, in the
banks of the hedge-rows the great sheet-webs and tubes of _Agelena_,
a near relative of the house-spider, but with a cobweb, thanks to its
situation, comparatively free from accumulations of dust and filth.
The creatures skipping, dry-shod, on the surface of the river or
pond, though often called water-spiders, are true insects. The real
water-spider, _Argyroneta_, which, though air-breathing, spends most of
its time below the surface of the water, is not to be found everywhere,
but there are many riparian species which are semi-amphibious in their
habits and have no objection to a wetting.
Finally, turn into the wood and look carefully on the ground,
especially where last year’s leaves are still lying. You are certain
to see a few—and may very likely see countless myriads—of sober
coloured, rapidly moving “wolf-spiders” (Lycosidae), roaming in quest
of food. No stay-at-homes, these, but rovers, trusting to speed and
agility, and not to guile, for their food supply.
All the spiders we have observed so far are in active pursuit of their
daily business, but if we turn over stones, or logs, or look under
sheets of loose bark, we shall find others, quiescent for the moment,
but waiting for nightfall to begin their operations.
But we have probably seen enough to show that a pretty wide field for
investigation lies immediately at hand, and that a detailed study of
what we have cursorily glanced at will occupy us so long that we shall
have little time for considering the spiders of other lands. In the
first place, however, we had better make quite sure of what is meant by
a spider.